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www.elsevier.com/locate/jom
Journal of Operations Management 24 (2006) 779–790
Six Sigma: The role of goals in improvement teams
Kevin Linderman a,*, Roger G. Schroeder a,1, Adrian S. Choo b,2
a Operations and Management Science Department, Curtis L. Carlson School of Management,
University of Minnesota, 3-150 CarlSMgmt Building, 321-19th Avenue South, Minneapolis, MN 55455, USAb Rensselaer Polytechnic Institute, Troy, NY, USA
Received 1 May 2005; received in revised form 1 August 2005; accepted 3 August 2005
Available online 27 December 2005
Abstract
The tenets of goal theory have been well established as a motivation mechanism in the management literature. However, some
quality-management advocates, such as W. Edwards Deming, often criticize the use of goals. This research investigates the tension
between goals and quality management in the Six Sigma context. We find empirical support that goals can be effective in Six Sigma
improvement teams when teams adhere to the Six Sigma tools and method. However, challenging goals are counterproductive when
Six Sigma teams do not use the tools and methods rigorously. This research reconciles the differences between quality management
and goal theory by showing that the Six Sigma tools and method interact with goals.
# 2005 Elsevier B.V. All rights reserved.
Keywords: Quality management; Six Sigma; Goal theory; Teams; Process improvement
1. Introduction
Much has been written about quality management
over the last few decades (Ahire et al., 1995; Sousa and
Voss, 2002). Most of the research focuses on studying
quality-management practices and associated success
factors (Kaynak, 2003; Sousa and Voss, 2002). However,
research on how motivational factors influence quality-
management outcomes is scant. Motivation is the process
that accounts for an individual’s intensity, direction, and
persistence toward a goal (Robbins, 2003, p. 155). While
goal theory research suggests that specific, challenging
goals lead to higher performance (Locke and Latham,
1990), at least one quality-management authority has
expressed a conflicting view. For example, Deming
* Corresponding author. Tel.: +1 612 626 8632.
E-mail addresses: [email protected] (K. Linderman),
[email protected] (R.G. Schroeder), [email protected]
(A.S. Choo).1 Tel.: +1 612 624 9544.2 Tel.: +1 612 626 9723.
0272-6963/$ – see front matter # 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jom.2005.08.005
(1986) viewed arbitrary numerical goals as counter-
productive. Research in quality management from a goal-
theoretic perspective can help resolve these conflicting
viewpoints.
Reviews of the goal-setting literature have consis-
tently demonstrated the effectiveness of individual goal
setting on performance (Locke and Latham, 1990; Locke
et al., 1981). In fact, Miner (1980) rated goal theory
‘‘high’’ in both criterion validity and usefulness in
application. (Criterion validation indicates ‘‘how well
scores on a measure correlate with the criterion on
interest’’ (Singleton and Straits, 1993, p. 122). This gives
an indication of practicality or usefulness of a measure.)
Also Pinder (1984) said, ‘‘goal theory has demonstrated
more scientific validity to date than any other approach
on motivation . . .. Moreover, the evidence indicates that
it probably holds more promise as a motivational tool for
managers than any other approach.’’
Research on the effects of goals on group
performance, however, is still emerging. O’Leary-Kelly
et al. (1994) performed a quantitative meta-analysis of
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790780
goals in the group setting and found a significant
relationship between group goals and group perfor-
mance. None of the studies in their meta-analysis
considered the effect of goals on quality-improvement
teams. Quality-improvement teams are central to
quality improvement (Scholtes et al., 1996) because
effective teams can perform significantly better than a
collection of individuals (Mohrman et al., 1995;
Katzenbach and Smith, 1993). Setting challenging
group goals can promote team effectiveness (Locke and
Latham, 1990) because goals tell teams what needs to
be done and how much effort to expend.
Little research in quality management uses goal
theory. Some quality-management movements, such as
the Zero Defects, have argued for setting very high
goals. However, some quality thinkers have been
critical of the goal-theoretic perspective. For example,
Deming (1994, p. 41) said ‘‘. . . a goal that lies beyond
the means of its accomplishment will lead to
discouragement, frustration, and demoralization . . ..A numerical goal accomplishes nothing.’’ Deming
systematically rejected the use of goals as a source of
motivation (Carson and Carson, 1993). Deming’s
‘‘negative views on quantitative goal setting are at
odds with both the historical management prescriptions
and contemporary research on goal setting and
motivation’’ (Duncan and Van Matre, 1990, p. 5).
Carson and Carson (1993) compare and contrast
Deming’s views with goal theory and reconcile
differences when possible. Hackman and Wageman
(1995) considered research issues related to quality
management and noted, ‘‘It is not surprising that there is
disagreement among the TQM authorities about goal
setting, because the nature of the work done by quality
teams raises some complex issues about how goals and
objectives are properly framed.’’ The conflicting views
of goals in quality management (e.g. Deming versus
Zero Defects) suggest the need for more scholarly
investigation. Empirical testing of goal theory in the
quality context can help reduce the confusion between
goal theory and quality management.
Recently, Linderman et al., (2003) developed a set of
propositions about Six Sigma from a goal-theoretic
perspective. Schroeder et al., (2003) provide a definition
of Six Sigma and compare it with other quality-
management approaches. These researchers argue that
nothing is radically new in Six Sigma but Six Sigma
does place a strong emphasis on challenging specific
goals (see also Pande et al., 2000). In fact, the name Six
Sigma suggests a goal of 3.4 parts per million defective.
The Six Sigma approach to process improvement also
employs numerous goals; for example, setting project
improvement goals to increase performance by a factor
of 10 (10�), hiring Black Belts on the basis of cost-
saving goals, and selecting improvement projects based
on financial and strategic goals. As a result, Six Sigma
provides an ideal context to study the relationship
between goal theory and quality management. Our
research begins to test the tenets of goal theory in Six
Sigma projects. Because Six Sigma is consistent with
quality-management principles, these results should
also be generalizable to other quality practices.
2. Theoretical development
Goal-setting theory suggests that challenging goals
lead to enhanced performance because they mobilize
effort, direct attention, and encourage persistence and
strategy development (Locke and Latham, 1990).
According to goal-setting theory, goals are effective
because they indicate the level of performance that is
acceptable (Locke and Latham, 1990). Specific goals
are critical to individuals because they establish a
minimum acceptable performance level, but ambiguous
goals either do not make clear the appropriate
performance level or indicate to individuals that a range
of performance levels is acceptable (Locke and Latham,
1990). Difficult goals, if accepted, lead to greater
individual effort and persistence (Locke and Latham,
1990; Locke et al., 1981; Tubbs, 1986). However,
assuming that the results of goal theory for individuals
also apply to groups may be subject to the ecological
fallacy (Singleton and Straits, 1993, p. 69). The eco-
logical fallacy can occur when erroneous information
from one level of aggregation (e.g. individuals) is used
to draw inferences about another level of aggregation
(e.g. groups). In this setting, the effect of goals motivating
individuals may differ from that of groups. As a result,
further research needs to be conducted at the group
level in goal theory (Weingart and Weldon, 1991).
In response to this phenomenon, scholars have been
studying goal theory in group settings (Weingart and
Weldon, 1991; Weldon et al., 1991; Weingart, 1992;
O’Leary-Kelly et al., 1994; Durham et al., 2000; Knight
et al., 2001). In general, scholars have found a
significant relationship between group goals and group
performance (O’Leary-Kelly et al., 1994; Locke et al.,
1997). Goal theory also suggests that specific goals
result in higher levels of performance than vague non-
quantitative goals such as ‘‘Do best’’ goals (Locke and
Latham, 1990). ‘‘Do best’’ goals are goals that are
implied by the task or occur when the subject is told to
do the best he or she can. O’Leary-Kelly et al. (1994)
found that goal specificity also applies to group goals.
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790 781
Fig. 2. Goal level and performance.
Six Sigma is known for employing specific challen-
ging process improvement goals (Pande et al., 2000). In
fact, Pande et al. (2000, p. 44) indicates, ‘‘A clear goal is
the center piece of Six Sigma. It is extremely
challenging, but still believable.’’ Quantitative improve-
ment goals used in Six Sigma included setting target
levels for defects per million opportunities (DPMO)
and/or Process Sigma. The 10� rule is one common
approach used in Six Sigma to establish improvement
goals. For example, if the current DPMO is 30,000 for a
process, the improvement goal is to reduce the DPMO
by a factor of 10–3000.
Fig. 1 illustrates the proposed relationship between
Six Sigma and goals under investigation in this research.
The figure indicates a direct effect of challenging and
explicit goals and a direct effect of the Six Sigma Tools/
Method on team performance along with a moderating
effect or interaction between goals and Six Sigma. These
proposed effects are explained below.
Although explicit challenging goals can lead to
higher performance, a drop in performance can occur
if goals become too challenging (Erez and Zidon,
1984). If goals are viewed as unattainable, individuals
may exert less effort, which would decrease
performance (Erez and Zidon, 1984; Locke and
Latham, 1984). Erez and Zidon (1984) found a
bipolar relationship between goals and performance.
When reviewing the literature goal difficulty and
performance relationship Locke and Latham noted,
‘‘in all cases goals are linear except when subjects
reach the limits of their ability at high goal difficulty
levels’’ (1990, p. 27). OM scholars have also argued
for considering bipolar (or non-linear) relationships
when applying behavioral theory to operations
management phenomena (Bendoly and Hur, 2005).
In Six Sigma, excessively challenging goals could
risk being viewed as unattainable and thus exhibit a
non-linear relationship between goal difficulty and
performance. Fig. 2 illustrates that challenging Six
Sigma goals lead to higher performance; however,
Fig. 1. Six Sigma and goals.
when goals become excessive, performance actually
declines.
Hypothesis 1. The degree of challenging goals used in
a Six Sigma project improvement team is concavely
related to project performance.
Research in goal theory suggests that the ability to
achieve goals moderates the relationship between goals
and performance (Locke, 1982). Goal theorists have
argued that difficult goals on complex tasks may
actually prove to be more detrimental to performance
than assigning no goals at all because they may create a
level of anxiety that interferes with goal accomplish-
ment (Earley et al., 1989). This perspective is consistent
with the views of some quality-management authorities.
According to Deming, ‘‘A numerical goal accomplishes
nothing. What counts is the method—by what
method?’’ (Deming, 1994, p. 41). Quality management
has advocated the use of quality tools and methods in
problem solving (Breyfogle, 1999; Gitlow et al., 1995;
Hoerl, 1998; Ishikawa, 1985; Kume, 1985, 1995;
Mizuno, 1988). Using quality improvement tools and
methods should reduce the task’s complexity by guiding
the search for solutions to complicated problems,
which, in turn, facilitates goal achievement.
Six Sigma advocates rigorous application of the
quality tools in each step of the problem-solving
methodology (Schroeder et al., 2003; Sanders and Hild,
2000). In Six Sigma, prescriptive tools are suggested for
each step in the improvement methodology (Rath and
Strong, 2000). Using Six Sigma tools and method
provides a mechanism for improvement teams to
achieve their goals, especially for challenging projects.
As a result, the degree to which Six Sigma teams adhere
to the tools and method should alter their ability to
achieve improvement goals, more so when goals are
challenging then when they are easy to achieve.
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790782
Hypothesis 2. The degree that Six Sigma teams adhere
to the use of tools and method positively moderates the
effect of challenging goals on project performance.
The application of quality tools and methods is
grounded in rational decision-making (March, 1999;
Harrison, 1999). Rational decision-making emphasizes
a systematic step-by-step approach to problem solving.
Handfield et al. (1999) found that appropriate use of
quality tools can lead to improved performance. To the
degree that improvement teams follow the Six Sigma
tools and method they can make better decisions, which
improves project performance. Furthermore, this is
consistent with prior research that suggests the degree
of implementation of quality practices is positively
related to organizational performance (Douglas and
Judge, 2001).
Hypothesis 3. The degree of adherence to Six Sigma
tools and method is positively related to project per-
formance.
3. Methods
3.1. Research environment
The primary source of data for this study comes from
a high-tech manufacturing firm using Six Sigma that we
refer to as MFG. MFG is a Fortune 500 company with
more than 60,000 employees worldwide. This leading
manufacturer of electronic components has annual
revenue of more than US$ 6 billion. It has been using
Six Sigma for 3 years and is very advanced in its
application. At the time of this research, MFG had about
200 full-time Black Belt specialists and had completed
more than 1500 Six Sigma projects, resulting in savings
of more than US$ 400 million from its Six Sigma
efforts. Black Belts are highly trained full-time
specialists in process improvement who receive more
than 4 weeks of training and hands-on project
improvement experience. MFG is also training most
of its employees in Six Sigma basics. These individuals
receive 2 weeks of training and are called Green Belts.
In MFG, each Six Sigma project is assigned a team of
employees who have substantial knowledge of the
process or product to be improved. They serve on a part-
time basis and often have Green Belt training. A full-
time Black Belt specialist leads each of these teams.
The Black Belt usually reports to the team sponsor,
called a Champion, who is from senior management and
is trained in Six Sigma basics. The Champion provides a
holistic view of the organization, which helps establish
project buy-in and ensures the availability of resources
to the team. Most projects have a target savings of at
least US$ 175,000, but this savings target does not
necessarily apply to all projects. Some projects may
have zero financial savings but generate other important
strategic benefits that are difficult to quantify in
financial terms.
Six Sigma project improvement teams at MFG
employ a structured improvement method and use
numerous quality tools. In MFG, the structured
improvement approach is called DMAIC (Define,
Measure, Analyze, Improve, Control). This approach
is patterned after PDCA (Plan, Do, Check, Act). In each
improvement step, standard quality tools like failure
modes effects analysis (FMEA), cause–effect charts,
and Statistical Process Control are used. These tools
include many of the seven classic tools of quality
control and the seven new tools for problem formulation
and diagnosis (Gitlow et al., 1995).
3.2. Data collection
A questionnaire was developed to collect data from a
sample of MFG’s 1500 completed Six Sigma projects.
Most recently completed projects by the Black Belts
were selected to minimize the measurement error due to
recency effect. That is, the sampling time frame
considered only projects completed with in the last 6
months to avoid problems associated with memory loss.
Because Black Belts came from different business units
in MFG, the projects selected were fairly random and
representative of the population of all completed
projects at MFG at the time of survey. Black Belt
and team members from each selected project were
invited to participate in this survey. Using multiple
informants reduced the common method bias and
increased validity compared with a single-informant
survey design.
The questionnaire was divided into parts: Black
Belts answered one part of the survey that contained
questions about performance. Team members answered
the other part of the survey about goals, tools, and
method. To a certain extent, the separation of theoretical
constructs into different parts of the survey further
reduced the common respondent bias while at the same
time reduced the number of questions per survey, which
tended to increase the response rate.
The survey was web-based: personalized email
invitations to participate in the survey were sent out by
the Vice President and Executive Director for Six Sigma
to 1233 team members and Black Belts from 324
projects. Each personalized email had a customized link
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790 783
that brought the respondent directly to the survey for a
specific project. Extra efforts were made to ensure
confidentiality and avoid the negative effects of Social
Desirability Bias (Nunnally and Bernstein, 1994).
Responses collected via the Internet were stored in a
protected Microsoft Access database. Follow-up remin-
ders and thank-you emails were sent every week for 3
weeks before we concluded the data collection with a
satisfactory number of responses. Some 951 persons
completed the survey for about a 77% response rate. At
the project-level, we collected data for 206 projects,
which represents a 63.5% response rate. The data for
each project are based on responses from the Black Belt
and at least two team members.
3.3. Variables and measures
Although we had multiple informants for all
projects, not all theoretical constructs had multiple
responses. The Performance construct had multiple
responses from Black Belts and at least one team
member for all projects, while other constructs had
multiple responses from only a third of the projects. We
assessed the inter rater reliability (IRR) (James et al.,
1984) and deleted 18 projects with inconsistent
responses (i.e. IRR � 0, >1) and low agreement (i.e.
IRR < .10). The remaining 188 projects had an average
IRR greater than 0.87 for all constructs with multiple
responses. We also compared, using a one-way
ANOVA, within-project variance and between-project
variance for the various constructs. F-statistics indi-
cated significant differences for between-project var-
iances. Although we did not have multiple responses for
all constructs, the results of the two tests showed
sufficient evidence that the data were consistent at the
project-level and that it was appropriate to aggregate the
item scores for theoretical constructs with multiple
responses. We aggregated multiple responses by taking
averages for the respective item scores in each project to
arrive at a sample of 188 projects. Then we removed all
projects designated as a Design For Six Sigma (DFSS)
because these projects require a methodology different
from the DMAIC that traditional Six Sigma projects
use. Finally, we removed all projects that involved
‘‘soft’’ dollar-savings and considered only ‘‘hard’’
dollar-saving projects. Soft dollar-savings projects are
often tied to the firm’s long-term strategy, which often
makes assessing performance difficult. This process
resulted in a total of 128 projects.
While quality-management measurement scales
existed in prior research (e.g. Saraph et al., 1989),
none was useful for this research, which required scales
for project improvement goals, project performance,
and adherence to Six Sigma tools and method. The
researchers developed the scales based on a literature
review and revised the scales through a pilot study at
MFG. All multi-item measures in this study use 7-point
Likert scales that ranges from 1-strongly disagree to 7-
strongly agree. The scales were pre-tested through a
pilot study at MFG by six Black Belts and eight team
members. Five university researchers also knowledge-
able in Six Sigma pre-tested the instrument. The pilot
study assessed three main characteristics of the
survey—clarity (i.e. is the question clear and easy to
answer?), content (i.e. does the question make sense and
is it appropriate?), and the average time taken to answer
the questionnaire. Appendix A provides a summary of
the scales.
3.3.1. Team project goals
Team project goals consisted of three items. This
scale had an alpha of 0.59 (Cronbach, 1951). New scales
often result in lower alphas making this scale minimally
acceptable for further use (Carmines and Zeller, 1978).
Using principle component analysis (PCA), the
resultant eigenvalue associated with this scale is 1.6,
above the minimum acceptable level of 1.0, and
explains 54.9% of the variation. All items loaded into
a single factor and the factor loadings for each item
ranged from 0.633 to 0.791, all above the acceptable
lower bound of 0.4 (Carmines and Zeller, 1978).
3.3.2. Six Sigma Tools/Method
Six Sigma Tools/Method consisted of four items.
This scale had an alpha of 0.68 (Cronbach, 1951), which
is considered acceptable. Using principle component
analysis, the resultant eigenvalue associated with this
scale is 2.056 and explains 51.4% of the variation. All
items loaded into a single factor and the factor loadings
for each item ranged from 0.631 to 0.814.
3.3.3. Team performance
Team performance consisted of five items. This scale
had an alpha of 0.90 (Cronbach, 1951). Using principle
component analysis, the resultant eigenvalue associated
with this scale was 3.659 and explained 73.2% of the
variation. All items loaded into a single factor and the
factor loadings for the items ranged from 0.784 to
0.919.
All of the scales were evaluated using principle
components analysis. For each scale factor scores were
created using the regression method. ‘‘Conceptually the
factor score represents the degree to which each
individual scores high on the group of items that have
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790784
Table 1
Correlations
Variable Mean S.D. 1 2 3 4
1 Project
Performance
4.09 0.56 1.00
2 Domestic 0.16 0.37 �0.33* 1.00
3 Goals 2.01 0.41 �0.11 �0.08 1.00
4 Six Sigma 3.07 0.41 0.38* �0.13 0.13 1.00
* Correlations significant at level P < 0.01.
high loadings on a factor. Thus, higher values on the
variables with high loadings on a factor will result in a
higher factor score’’ (Hair et al., 1998, p. 119). The
factor scores provide the basis for subsequent analysis.
3.3.4. Control variable
Discussion with MFG executives indicated that there
might be a difference in performance of Six Sigma
projects between domestic and international sites.
Domestic sites were more involved in R&D efforts
and production was often initiated domestically, then
transferred to international sites. MFG also observed a
lot of enthusiasm for Six Sigma from the international
sites; people at the domestic sites tended to be more
skeptical. Scholars have noted the importance of
considering the international context when studying
operations management (Prasad and Babber, 2000),
which suggests the need to control for domestic versus
international location.
4. Results
Mean, standard deviation, and correlations of the
variables under consideration are displayed in Table 1.
The collinearity diagnostics (including Variation Infla-
tion Factors) indicate that multicollinearity is not a
problem. A significant correlation exists between Team
Performance and Six Sigma and between Team
Performance and Domestic Projects.
Table 2 provides the results of the regression
analysis. Model 1 gives the regression of the control
variable on the Project Performance variable, which is
significant (F = 15.541, P < 0.001). Model 2 adds in
the main effects of Six Sigma Tools/Method and Goals,
Table 2
Regression analysis for Six Sigma goals and performance
Variable Model 1 Model 2
b t b
Domestic �0.891 �3.942*** �0.796
Goals �0.180
Goals2 �0.007
Six Sigma Tools/Method 0.355
Six Sigma Tools/Method � Goals
Six Sigma Tools/Method � Goals2
R2 0.11 0.251
F 15.54*** 10.298***
DR2 0.141***
* P < 0.1.** P < 0.05.
*** P < 0.001.
this also gives a significant model (F = 10.298,
P < 0.001) and suggests the main effects influence
Project Performance. Also, the R2 improves by 0.11 in
Model 2, but the Goals2 term is not significant. Model 3
adds in the interaction terms between Goals and Six
Sigma Tools/Method. The model is significant
(F = 7.798, P < 0.001) and the R2 improves by
0.028. Model 4 in Table 2 drops the non-significant
predictor variables (Goals2, Six Sigma Tools/Meth-
od � Goals2) from the regression equation. This model
is also significant (F = 11.669, P < 0.001) along with
all the predictor variables. We removed the non-
significant terms because they can alter the interpreta-
tion of the model (Neter et al., 1996, p. 308). Regression
diagnostics indicate no problems with outliers, normal-
ity, or homoscedasticity. We find that the R2 of 0.275 is
acceptable given the limited number of variables used to
predict performance. Subsequent analyses are con-
ducted on Model 4.
Model 4 suggest that performance of domestic
projects is significant and results in lower performance
than international projects (t = �3.736, P < 0.001), All
other models (Models 1–3) give similar conclusions.
These results are consistent with our expectations that
Model 3 Model 4
t b t b t
�3.672*** �0.797 �3.711*** �0.830 �3.736***
�2.278** �0.164 �2.007** �0.160 �2.042**
�0.149 �0.034 �0.602
4.470*** 0.347 3.683*** 0.355 4.546***
0.155 2.166** 0.138 2.032**
0.004 0.081
0.279 0.275
7.798*** 11.669***
0.028*
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790 785
international Six Sigma projects had a higher level of
performance than domestic projects at MFG.
Interpreting the other coefficients of the regression
model is more difficult. Without interactions, the
coefficients of the regression equation indicate the
change in mean response with a unit increase in
the predictor variable. However, the meaning of the
coefficients is not the same in the presence of
interaction terms (Neter et al., 1996, p. 308). Model
4 indicates a significant interaction between Goals and
Six Sigma Tools/Method (t = 2.032, P < 0.001). In this
setting, the mean response, E [Project Performance],
with a unit increase in Goals when Six Sigma Tools/
Method is held constant and given by the following:
E ½Pro ject Per formance�
¼ �0:16þ 0:138 ðSix Sigma Tools=MethodÞ
Similarly, with a unit increase in Six Sigma Tools/
Method and Goals held constant is given by the
following:
E½Pro ject Per formance� ¼ 0:355þ 0:138ðGoalsÞ
The conditional effects plot (Neter et al., 1996, p.
310) provides a way to interpret the regression equation
in the presence of an interaction effect. Fig. 3 gives the
conditional effects plot for E [Project Performance] as a
function of Goals conditioned on Six Sigma Tools/
Method. The plot considers values between the 1st and
99th percentile ranking for goals, conditioned on the
1st, 50th, and 99th percentile ranking of Six Sigma
Tools/Method. In general, the conditional effects plot
indicates that when Six Sigma Tools/Method is low,
challenging goals result in lower performance. How-
ever, when Six Sigma Tools/Method is high, challen-
ging goals result in higher performance. As a result, Six
Fig. 3. Goal difficulty cond
Sigma Tools/Method has a reinforcement or synergistic
(Neter et al., 1996, p. 311) effect on goals.
Similarly, Fig. 4 provides the conditional effects plot
for E [Project Performance] as a function of Six Sigma
Tools/Method conditioned on Goals. The plot considers
values between the 1st and 99th percentile ranking for
Six Sigma Tools/Method, conditioned on the 1st, 50th,
and 99th percentile ranking of goals. An equivalent
story emerges where increasing Six Sigma Tools/
Method results in lower performance when goal
difficulty is low. However, when goal difficulty is high,
increasing Six Sigma Tools/Method results in higher
performance.
The conditional effects plots (Figs. 3 and 4) and the
statistical significance of the interaction term in Table 2
support Hypothesis 2. That is, empirical evidence
indicates that Six Sigma Tools/Method positively
moderates the effect of challenging goals on project
performance.
We are unable to fully support Hypotheses 1 and 3 as
stated, since there is a significant interaction term in
model 4 that makes it difficult to interpret the main
effects. This is because the main effects are conditioned
by their interaction with another variable. That is, the
effect of goals is conditioned on the level of Six Sigma
Tools/Method and visa versa. The conditional effects plot
in Fig. 3 indicates partial support for Hypothesis 1.
Increasing goals linearly improves performance when
teams make extensive use of Six Sigma Tools/Method.
However, we found no support for the quadratic
relationship between goals and performance as suggested
in Fig. 2. Possibly all Six Sigma projects sampled in this
survey did not have goals that were viewed unrealistic
and unattainable, which in turn could have reduced
motivation and lowered performance outcomes.
The conditional effects plot in Fig. 4 also gives
support to Hypothesis 3. The use of Six Sigma Tools/
itioned on Six Sigma.
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790786
Fig. 4. Six Sigma conditioned on goal difficulty.
Method results in higher performance except when
goals are low. One reviewer noted the anomaly that
extensive use of Six Sigma Tools/Method actually
resulted in lower performance when goals are low.
There could be an explanation for this outcome. In
discussions with Six Sigma consultants, they note that
sometimes organization inappropriately apply the Six
Sigma Tools/Method. As the adage goes ‘‘if you have a
hammer, everything looks like a nail.’’ Teams can waste
valuable time and effort rigorously applying Six Sigma
Tools/Method when the solution is obvious. In this
situation, the excessive use of Six Sigma Tools/Method
can actually reduce performance. As suggested by one
consultant, the solution method should fit the problem.
This consultant advocates the use of a Do-It project
when the solution is obvious and the focus is on
implementation. (A Do-It project means take action
immediately, there is no need for a root cause analysis.)
This consultant argues that a Six Sigma project should
only be used when the solution is not clear (that is, root
cause analysis is required). Possibly projects that have
low goals should have been Do-It projects rather than
Six Sigma projects, which would be consistent with the
results in Fig. 4.
5. Discussions and conclusions
5.1. Theoretical implications
This study addresses the role of goals in Six Sigma
project improvement teams. To the extent that Six
Sigma reflects quality-management practices in gen-
eral, this research should be generalizable to other
quality-management approaches. We found empirical
support that goals do in fact affect project performance.
However, analysis shows a positive interaction effect
between Goals and Six Sigma Tools/Method with
performance. This supports the perspective advocated
by some quality-management authorities. As Deming
(1994, p. 41) said, ‘‘. . . a goal that lies beyond the means
of its accomplishment will lead to discouragement,
frustration, demoralization. A numerical goal accom-
plishes nothing. What counts is the method—by what
method?’’ The results of this research are consistent
with Deming’s perspective. Goals can have a positive
effect on performance when used with Six Sigma Tools/
Method. As Carson and Carson (1993) note, ‘‘Deming
and traditional theorists are often arrayed on opposing
sides. The truth, though, is somewhat different.’’ This
research provides empirical support that Deming and
goal theory can be reconciled.
Little empirical research has been done using goal
theory in operations management and quality manage-
ment in particular (Linderman et al., 2003), a surprising
fact given that goal theory is a well-established
management theory (Locke and Latham, 1990; Pinder,
1984; Miner, 1980). Incorporating theories from
organizational behavior can help inform the practical
consequences of implementing operations management
practices. In this setting, we find that behavioral theories
interact with technical tools and method in interesting
ways; that is, the use of technical tools and motivational
factors must be managed jointly rather than in isolation.
More broadly, operations management should not be
understood as a purely technical problem but must be
considered simultaneously with behavioral underpin-
nings. Recently operations management scholars have
recognized that ‘‘incorporating human behavior into
OM models will yield more realistic insights’’
(Boudreau et al., 2003). Some scholars have begun to
examine the behavioral implications of technical tools
in operations management (Doerr et al., 1996;
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790 787
Rungtusanatham, 2001; Schultz et al., 1998). Our
research helps advance this effort.
This research also contributes to goal theory.
Although goal theory is well established for individuals,
it is still developing for groups (Locke and Latham,
1990; Weingart and Weldon, 1991; Weldon et al., 1991;
Weingart, 1992; O’Leary-Kelly et al., 1994). Little goal
theory research has considered different types of groups
(O’Leary-Kelly et al., 1994). Most studies consider
work-teams where group membership is stable and
employees work together on a daily basis. To our
knowledge, this is the first study to consider problem-
solving groups (Six Sigma teams) and goals. In this
setting, problem-solving teams are formed to solve a
problem and then disbanded upon completion of the
project. We also consider the influence of using
problem-solving tools and method on goals, which
other goal theory studies have not considered.
5.2. Managerial implications
Quality-management practices can often become the
latest management fad (Abrahamson, 1996), which can
also create distortions between the rhetoric and reality
of what is practiced (Zbaracki, 1998). Managers may set
high goals when deploying quality but may not follow
through on fully implementing the prescribed techni-
ques. Based on this research, setting challenging goals
without fully utilizing the tools and method can lead to
sub-optimal results. Organizational leaders need to
make sure that quality-improvement teams are, in fact,
using the tools and method espoused by quality theorists
and practitioners. For example, MFG developed a
Project Evaluation System that performs a pre- and
post-project review of the improvement projects to
assess the appropriate use of the tools and method. The
Project Evaluation System helps make sure that
improvement teams use the tools and methods in the
prescribed fashion. Using these deployment techniques
not only ensures proper use of tools and method but also
facilitates achievement of project improvement team
goals.
Recently, Steve Kerr, Chief Knowledge Officer at
General Electric, noted ‘‘Most organizations do not
have a clue about how to manage stretch goals. It is
popular today for companies to ask their people to
double sales or increase speed to market threefold. But
then they do not provide their people with the
knowledge, tools, and means to meet such ambitious
goals’’ (Sherman, 1995, p. 231). This research supports
the belief that challenging goals must be supplemented
with tools and method to solve difficult problems. Kerr
further suggested that giving employees challenging
goals without a means to achieve them is immoral
(Sherman, 1995). In the quality context, leaders need to
be cognizant of the importance of training and
supporting the use of problem-solving tools and
methods. Otherwise, challenging improvement goals
could demoralize employees involved in Six Sigma
projects.
Organizational leaders pursuing quality practices
often take a rational approach to improvement of the
organizational system (Kast and Rosenzweig, 1972).
Improvement of rational systems (Scott, 1987) is
governed by both knowledge and motivation. Without
knowledge, improvement only occurs by chance events
that are rarely understood. In Six Sigma, the creation of
knowledge occurs through intentional or explicit
learning that employs formal improvement methods.
Intentional learning requires regulation of actions taken
by organizational members. Goals serve as regulators of
human action by motivating project improvement
teams. Thus, improvement goals motivate teams to
engage in intentional learning activities that create
knowledge (Linderman et al., 2003). As a result,
organizational leaders that make effective use of goals
can regulate how much organizational knowledge is
created through Six Sigma.
Also, organizations often use heuristics when setting
goals for project improvement teams. One common
heuristic used in Six Sigma is the 10� rule, which sets
an improvement goal of reducing defects by a factor of
10 (Harry and Schroeder, 2000). However, from a goal
theory perspective, such heuristics may not be effective.
If managers do not ensure teams are trained and use the
appropriate problem-solving tools, challenging goals
might actually lead to lower performance.
5.3. Limitations and conclusions
Despite the interesting results of this study, several
limitations need to be emphasized. First, the study
considered data from a single firm. Although this does
help control for confounding factors like organizational
culture, it lacks external validity. Further replications of
this study are required to fully test the theory.
Second, factors such as group cohesion (Levine and
Moreland, 1990) and social loafing (Price, 1987) were
not considered. These contextual variables could
influence a team’s ability to achieve goals; however
to date, they have not been tested (O’Leary-Kelly et al.,
1994). As research on goal theory in a group setting
matures, we should better understand contextual
variables in teams that influence goal achievement.
K. Linderman et al. / Journal of Operations Management 24 (2006) 779–790788
Third, other types of improvement projects beyond
Six Sigma were not considered. Possibly the type of
improvement project employed could effect the
relationship between goals and performance. For
example, the Do-It project discussed earlier could have
a different effect on the relationship between goals and
performance. Other improvement approaches such as
Lean were also not considered. Possibly using alter-
native improvement tools/methods has a different effect
on relationship between goals and performance.
Fourth, the role of national culture is not considered.
Possibly, different national cultures affect how goals
and Six Sigma Tools/Method affect performance. One
reviewer noted that this relationship could be investi-
gated by examining the interaction effects of the
Domestic variable with all other variables in the model.
However, this created significant multicollinearity
problems that made interpretation of the coefficients
impossible. Future research can study the effect of
national culture on these relationships in more depth.
Finally, project size and duration, prior group project
experience, or project group size could also affect
performance. Variation of these variables at MFG were
somewhat limited since they typically scoped projects
to last between 4 months and half a year, and each
project had typically four to six team members. In
addition, they had a 2-year rotation system for Black
Belts, which meant that Black Belts had a 2-year
assignment in Six Sigma and then were re-integrated
back into the regular organization. This would control
somewhat for prior experience with respect to Black
Belts. As a result, these variables were somewhat fixed
at MFG. Future research could investigate how changes
in these variables influence performance.
Despite the limitations, this study makes several
important contributions. Notably, it helps to clarify the
controversial relationship that goal theory has had with
quality-management authorities. It shows that goals can
be effective when used with quality tools and method.
This is particularly important for Six Sigma, which has
a strong goal orientation toward improvement (Linder-
man et al., 2003). In addition, very little research in
operations management has considered goal theory
(Boudreau et al., 2003). This is surprising given that
goal theory is well established in the management
literature (Locke and Latham, 1990). This research
helps illustrate that operations management is not just a
technical problem but also requires behavioral con-
sideration. Future research in operations management
should consider theories from organizational behavior.
Organizational behavior theories might serve to
enhance future research in operations management.
Or, this research has demonstrated the usefulness of
organizational behavior theories for future operations
management inquiries.
Acknowledgement
This research was supported in part by a National
Science Foundation Grant NSF/SES-0080318
Appendix A. Measurement scales
All responses range from 1-strongly disagree to 7-
strongly agree
Team project goals
1
We found it very difficult to achieve the project goals2
It was relatively easy to achieve the project goals(reverse scaled)
3
The project goals were challenging to usSix Sigma Tools/Method
1
The project strictly followed the sequenceof DMAIC steps
2
Each step in DMAIC was faithfully completed3
There was an emphasis on applying variousanalysis tools wherever applicable in this project
4
This team frequently used Six Sigma tools to analyzedata and information
Team performance
1
We met or exceeded customers’ expectations in this project2
This team had superb results on this project3
This team did not meet the project goals (reverse scaled)4
The cost savings or strategic impact of the projectwere significant
5
The project was effective in improving the process or productReferences
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