Efficient or Just Busy?

Pawel Brodzinski

@pawelbrodzinski

Hi, I’m Pawel

Lunar Logic http://llp.pl

Software Project Management http://brodzinski.com

Twitter @pawelbrodzinski

Once upon a time…

Why?

100% utilization

Cost of multitasking

Source: Gerald Weinberg, Quality Software Management: Vol. 1 System Thinking

Zeigarnik Effect: Tendency to experience intrusive thought about

an objective left incomplete

Source: S. Greist-Bousquet, N. Shiffman: The effect of task interrupton and closure on perceived duration

Cost of task switching is rooted in interference from thoughts about the task your are not doing

Eyal Ophir

Time to market

Catching up UM… HOW DOES THIS DARN CODE WORK,

AGAIN?

More mistakes

Source: E. Ophir, C. Nass, A. Wagner: Cognitive control in media multitaskers

On a highway

In a call center

Ball Flow

Game

No WIP Limits

Using WIP Limits

Total time: 25% better

Average cycle time: 60% better

Predictability*: 90% better

*Standard deviation

Not the whole truth

Cutting corners

Not sustainable

Why something that intuitive seems so counterintuitive when we talk about management?

…and they lived happily ever after

5O

WIP limits!

Average cycle time: 50% better

Pessimistic scenario: 53% better

Predictability*: 65% better

*80th percentile

Why?

Slack time

Automation

Code quality

Simple configuration

Self-balancing team

Slack time introduced by WIP limits drives continuous

improvement

When introducing WIP limits start with 2x average WIP

Don Reinertsen

Cost of rejected work: 1% worse

Cost of idle capacity: 1% worse

Average cycle time: 28% better

Source: Don Reinertsen, #lkce12 keynote

WIP Limit = 2x Average WIP

Cost of rejected work: 13% worse

Cost of idle capacity: 11% worse

Average cycle time: 72% better

Source: Don Reinertsen, #lkce12 keynote

WIP Limit = 0.5x Average WIP

Are aggressive WIP limits useful?

2O

What’s the use of slack time?

Idle time only?

Helping others

Learning

System improvements!

Cost of rejected work

What’s the value of rejected work?

More than a half the features in large software products go unused

Source: Victor R. Basili, Barry Boehm, COTS-Based Systems Top 10 List

Cost of idle capacity

Is that capacity really wasted?

Employees possess the ability for creative problem solving, but their talents are underused in most organizations

Source: Douglas McGregor, Theory Y

Average cycle time

What happens to cycle time thanks to improvements?

CO

ST O

F DEL

AY

LONG-TERM VALUE

CO

ST O

F DEL

AY

Project and product

work

LONG-TERM VALUE

CO

ST O

F DEL

AY

Project and product

work System

improvements

LONG-TERM VALUE

CO

ST O

F DEL

AY

Project and product

work System

improvements

LONG-TERM VALUE

Takeouts

100% utilization is a myth

1OO%

Introducing WIP limits results in improved efficiency

Slack time sets us on path of continuous improvement

Efficient doesn’t mean busy Busy doesn’t mean efficient

Thank you

Pawel Brodzinski

blog.brodzinski.com

llp.pl

@pawelbrodzinski