5. The Spectrum of Estimating
Never
Estimate
Anything
Always
Estimate
Everything
Question purpose of estimating
Include all sources of variation
Focus on characterizing work
Probabilistic forecast
Use delivery data
Less effort spent
Estimation culture
Consider effort only
Deterministic forecast
Use intuition
Heavy effort involved
Tasks in hours
#leanagileUS @mattphilip
6. What NoEstimates is not saying
• You are evil if you estimate
• All estimates are totally useless
• Stop doing your successful estimating practice
• Stop having the conversations to understand/analyze/break down work
• Work items must be the same size
• You must place your full faith and confidence in Monte Carlo forecasts
#leanagileUS @mattphilip
7. What NoEstimates is saying
• Know why you are estimating
• Discover for yourself how good you are at estimating (measure)
• Keep doing the things that help you understand the work
• Upfront estimates need to be held loosely
#leanagileUS @mattphilip
8. NoEstimates, Manifesto Style
… We have come to value:
Probabilistic over Deterministic
Delivery time over Development time
MVP scope over Full scope
Data over Intuition*
Reducing sources of variation over Improving estimating
That is, while there is value in the items on the right, we value the items on the left more.
*Neil Killick uses “empiricism over guesswork”
#leanagileUS @mattphilip
10. Do You Assume Correlation?
Is the initial sizing a good predictor for when you can get your stuff?
In our case, the surprising truth was ”no.”
-- Mattias Skarin, Real-World Kanban
#leanagileUS @mattphilip
11. What’s Going On?
Low process efficiency (typically 5-15% in
software delivery) means that even if we
nailed the effort estimates … we would be
accurately predicting 5-15% of elapsed
delivery time!
-- Troy Magennis
#leanagileUS @mattphilip
12. Other Sources of Variation
Often system factors account for more of the elapsed delivery time than different
story sizes.
-- Troy Magennis
#leanagileUS @mattphilip
14. Sources of Variation
#leanagileUS @mattphilip
• WIP
• Technology/domain/product
• Team composition
• User, client and client representative
• Multitasking/focus factor
• Market and competitors
• System dependencies
• Team dependencies
• Specialization
• Waiting for availability
• Rework
• Steps/handoffs (50%*50%*50%...)
• Stages in team development (Tuckman)
• Selection policy
• Essential complication (How hard a problem
is on its own)
• Accidental complication (“How much we
suck at our jobs” -Rainsberger)
16. Keogh’s “Scale of Ignorance”
1. Just about everyone in the world has done this.
2. Lots of people have done this, including someone on our team.
3. Someone in our company has done this, or we have access to expertise.
4. Someone in the world did this, but not in our organization (and probably at a
competitor).
5. Nobody in the world has ever done this before.
#leanagileUS @mattphilip
17. What Can You Do About Variation?
#leanagileUS @mattphilip
How many remedies
can you name?
18. What You Can Do About Variation
• Lower WIP
• ConWIP/System WIP
• Five Focusing Steps
• Blocker clustering
• Reduce workflow stages
• Explicit policies
• Cost of Delay scheduling, sequencing and selection
#leanagileUS @mattphilip
Lean-Kanban
19. What You Can Do About Variation
• “Agile 101” (simple, decoupled design; thin vertical slices; pairing)
• Identify/make visible/measure dependencies
• Collaborate/Share work (Dimitar Bakardzhiev)
• Spike and stabilize (Dan North)
• Reduce accidental complexity (Liz Keogh)
#leanagileUS @mattphilip
Team
Why?
21. NoEstimates and the Business
• Determine what actions would be different based on the estimate
• Customer-based fitness criteria
• Budgeting: Team run rate
• Focus conversation on value, not cost
• MVP and product ownership
• Create probabilistic forecast ASAP (as soon as you have data) – together!
• Service-Delivery Reviews
• Teams: Keep teams together, dedicated (reduces context-switching, Tuckman stages)
#leanagileUS @mattphilip
22. To Estimate or Not to Estimate?
Never
Estimate
Anything
Always
Estimate
Everything
Question purpose of estimating
Include all sources of variation
Focus on characterizing work
Probabilistic forecast
Use delivery data
Less effort spent
Estimation culture
Consider effort only
Deterministic forecast
Use intuition
Heavy effort involved
Tasks in hours
#leanagileUS @mattphilip
A better question:
What can you do to maximize value and
reduce risk in planning and delivery?