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Software Technology Support Centergy pp
Why SoftwareWhy Software Projects Fail
Dr. Randall JensenLes Dupaix
Software Technology Support CenterHill AFB, UTHill AFB, UT
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Project success rateO G D E N A I R L O G I S T I C S C E N T E R
j
CHAOS 2004 S ft P j t SCHAOS 2004 Software Project Survey
Failed18%Success 18%Success
29%
Challenged53%53%
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CHAOS Success rate definitionsO G D E N A I R L O G I S T I C S C E N T E R
P d d t bl ltSuccess Produced acceptable results delivered close to on-time and on-budget
Challenged Delivered software product g psignificantly over budget and/or schedule
Failed Failed to deliver any usable result within budget orresult within budget or schedule constraints
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Software problems are not newO G D E N A I R L O G I S T I C S C E N T E R
p
UnreliableUnreliable
Late delivery
Modification costs prohibitive
Impossible to maintainp
Inadequate performance
P d t d b d t tProduct exceeds budget costs
1968CS Conference, Munich, Germany
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Reasons for project failureO G D E N A I R L O G I S T I C S C E N T E R
p j
ADVERTISEDADVERTISEDImmature technology
Inadequate requirements
Insufficient developer experienceInsufficient developer experience
COVERTPoor estimating and planning
Hope (Pandora’s paradox)Hope (Pandora s paradox)
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Repeatable thingsO G D E N A I R L O G I S T I C S C E N T E R
p g
Development environmentDevelopment environmentProductivityMi i d l t tiMinimum development time
Effective product sizeC l itComplexityPaul Masson rule
Let’s look at some proof
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BIG productivity driversO G D E N A I R L O G I S T I C S C E N T E R
BIG productivity drivers
A l t bilitAnalyst capabilityManagement styleM ti tiMotivationProblem solving skillsUse of team methodsUse of team methodsWorking environment
Application domain experienceApplication domain experience Automated tool support Programmer capabilityProgrammer capabilityUse of modern practices
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Capability shift (environment)O G D E N A I R L O G I S T I C S C E N T E R
1980 2005
8635(1990)
5500 750065006200Basic Technology Constant
85008000
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Basic Technology Constant
1996/2003 Productivity for Avionics and Unmanned Space
O G D E N A I R L O G I S T I C S C E N T E R
and Unmanned Space
1.0
0.8
velo
pmen
t...
0.6
softw
are
dev
0 5
0.2
0.4
bilit
y th
at th
e
Productivity (2003)Productivity (1996)50th percentile (2003)
0.5
0.00 50 100 150 200 250 300
Prob
ab 50th percentile (2003)50th percentile (1996)
47 64
..progressed at LESS THAN this rate in lines/developer-months1996 graph based on 52 Mil-Spec Avionics & Unmanned Space Softw are Data Records2003 graph based on 51 Mil-Spec Avionics & Unmanned Space Softw are Data Records
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Aerospace Corp – Long etal 2004
1996/2003 Productivity Distributions for Ground and Mobile
O G D E N A I R L O G I S T I C S C E N T E R
for Ground and Mobile
1.0..
0.8
velo
pmen
t.
0.6
oftw
are
dev
0 5
0.4
that
the
so
Productivity (2003)P d ti it (1996)
0.5
0.2
Prob
abili
ty Productivity (1996)
50th percentile (2003)50th percentile (1996)
0.00 100 200 300 400 500 600
...progressed at LESS THAN this rate in lines/developer-months
P
105 138
1996 graph based on 112 Military Ground & Military Mobile Softw are Data Records2003 graph based on 135 Military Ground & Military Mobile Softw are Data Records
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2003 graph based on 135 Military Ground & Military Mobile Softw are Data Records
Aerospace, Long et al, 2004
Common technology claimO G D E N A I R L O G I S T I C S C E N T E R
gy
If you use (new technology),
Productivity will improve by an order of magnitude
And
Defects will reduce to zero
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There is always HOPEO G D E N A I R L O G I S T I C S C E N T E R
y
100
90Ada
Structured AnalysisPRO 90
80 OOD
Structured DesignProcess Maturity
ODUC
70
OOD
PWB
TIV
60
50
W
Structured Programming3rd Generation Languages
ITY
1960 1970 1980 199050
lppm
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Where would you focus effort?O G D E N A I R L O G I S T I C S C E N T E R
3 TOOLS
11 PEOPLE
17 SYSTEMS17
64
SYSTEMS
MANAGEMENT64 MANAGEMENT
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Source: G. Weinberg, Quality Software Management, Vol. 3
Relative payoffO G D E N A I R L O G I S T I C S C E N T E R
70
60
70
40
50 SEI Papers
cent
30
40
Perc
10
20
Tools People Systems Managers0
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Source: G. Weinberg, Quality Software Management, Vol. 3
Repeatable thingsO G D E N A I R L O G I S T I C S C E N T E R
p g
Development environmentProductivityMinimum development time
Effective product sizeComplexityPaul Masson rule
Let’s look at more proof
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Historic project dataO G D E N A I R L O G I S T I C S C E N T E R
p j
Source: Long, L. G. et al, 2004
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g
Historic space project limitsO G D E N A I R L O G I S T I C S C E N T E R
Historic space project limits
200
Successful Completions
0
Time5 years0
0
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Source: Long, L. G. et al, 2004
Three development variablesO G D E N A I R L O G I S T I C S C E N T E R
p
Cost
Schedule
Scope
Developer can control any two
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p y
Historic note:O G D E N A I R L O G I S T I C S C E N T E R
“More software projects have More software projects have gone awry for lack of calendar time than for all other causes time than for all other causes combined…”
F. P. Brooks, Jr., Mythical Man Month
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Common estimate dilemma O G D E N A I R L O G I S T I C S C E N T E R
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Constraint analysisO G D E N A I R L O G I S T I C S C E N T E R
y
Success and failureSuccess and failure determined by
E t d t d h d lExpected cost and scheduledetermined by
Project plandetermined byy
Cost and schedule ESTIMATESdetermined bydetermined by
Managers and/or Estimators
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Key estimate factorsO G D E N A I R L O G I S T I C S C E N T E R
y
X
Start Here
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Elements for successful estimates
O G D E N A I R L O G I S T I C S C E N T E R
estimates
Basic understanding of the requirements
Ability to accurately size the deliverable product
Assessment of the deliverable complexityAssessment of the deliverable complexity
Profile of the organization’s delivery capability
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Estimates are importantO G D E N A I R L O G I S T I C S C E N T E R
p
Without well thought out estimates, there is no firm basis for:
Defining costs and schedulesMaking tradeoffsMaking tradeoffsAssociating development costs with the benefitsConforming to a budget or scheduleConforming to a budget or schedule
THE PROJECT IS ALREADY OUT OF CONTROL!THE PROJECT IS ALREADY OUT OF CONTROL!
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Project success rateO G D E N A I R L O G I S T I C S C E N T E R
j
CHAOS 2004 S ft P j t SCHAOS 2004 Software Project Survey
Failed18%Success 18%Success
29%
Challenged53%53%
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Success definitions: 2nd lookO G D E N A I R L O G I S T I C S C E N T E R
Success definitions: 2 look
Success Produced acceptable results delivered close to on-time
Challenged
and on-budget
Delivered software productChallenged Delivered software product significantly over budget and/or schedule
Failed Failed to deliver any usable result within budget or
h d l ischedule constraints
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ConclusionsO G D E N A I R L O G I S T I C S C E N T E R
Software project failures are primarily due to failedSoftware project failures are primarily due to failed expectationsTechnology, requirements and experience are largely accounted for in resource estimatesFailure ranking:
1. Poor estimating and planning2 Hope (Not a management strategy)2. Hope (Not a management strategy)3. Immature technology 4. Inadequate requirements5. Insufficient developer capability (Ebonians)
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New estimating models?O G D E N A I R L O G I S T I C S C E N T E R
g
Lack of confidence in existing toolsLack of confidence in existing toolsOptimistic estimatesUnacceptable estimatesUnacceptable estimates
•Skill •Experience I t it• Integrity
Aging toolsQuality dataQuality data Culture is constantNew models require validationNew models require validation
Silver bulletNew estimators?
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New estimators?
Historic note:O G D E N A I R L O G I S T I C S C E N T E R
We learn from We learn from experience that we don’t learn we don t learn from experience.
D. H. Lawrence
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O G D E N A I R L O G I S T I C S C E N T E R
The End, or
is itis itThe Beginning?
(History does repeat itself)( y p )
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