7. Estimates
⢠Traditionally Blamed for Project Failure
⢠We Donât Like Being Held to Them
⢠Blame Ensues
â âYou told me it would take this longâ (external)
â âI failed to hit my own deadlineâ (internal)
8. However, EstimatesâŚ
⢠Never Killed A Project!
â Variance Between Estimate & Actual Time/Cost Killed it!
⢠Set Expectations
â Uncertainty & Stakeholder Expectation Badly Managed
⢠Deliver one âhalfâ of Value Equation
â Like it or not, cost is the other
⢠Salaries, Recruitment, Capex, Opex, SaaSâŚ
⢠Stakeholders Donât Understand Variance
⢠Larger Estimates = Uncertainty Higher
⢠Humans Better At Smaller Estimates!
9. ACTIVITY: Audience Participation
⢠Score-sheet Coming
Round
1. Shown Patterns of Red
Dots for 2 seconds
2. Count/Estimate
Number of Dots
3. 5 Second Countdown
4. This will be repeated
10 times
5. Swap Scorecards &
Total Results
Yes, there is 3!
31. Relevant ConceptsâŚ
⢠Humans Naturally Remember (& Process) 5 to 9
items
â More Leads to Confusion & Complexity
â Less and Youâre Easily Confused :o)
â Stories of 8+ Points Need Breaking Down
⢠Regularity Makes Estimates Easier
â Low/Zero Variance
â Use Lessons Learned/Code Libraries As-is
â e.g. Squares Easiest to Estimate (measure one side
and square it)
32. HoweverâŚ
⢠Coderâs World is [Mostly]
Uncertain!!
⢠Regularity Doesnât Exist!
â No two projects/Components
are exactly the same.
⢠Usually > 9 items of
ANYTHING
â Components
â Classes
â Methods
â Lines of Code
⢠Continually look at points
distribution! Or do â1-pointâ
stories (e.g. #NoEstimates)
Time
Frequency
Actual Client Data
33. Tackling Uncertainty
⢠Split into Predictable Chunks, Then Aggregate
⢠Use Small Chunks - Lowers Variability (& Confusion)
⢠Beware Relationships! Any Relationship is Complex! Especially if Shared!
⢠Use what you know as a baseline and LEARN!
⢠= More âAccurateâ Delivery!
4 = 14,
4
3
3
= + = 10
9 1
34. Cone of Uncertainty
Large Chunk Project
(BDUF/RUP) = Long
Feedback Cycle. Slow
journey to certainty
Small Chunk Project
(Sprint/Iteration) =
Frequent Learning, Moves
towards Certainty,
Descends Cone Faster
Predictability
Time
Uncertainty Curve
KEY
35. So, Get Feedback Fast!
⢠Make Small Changes
⢠Change one thing!
⢠Deploy & Evaluate Efficacy
Bigger Tasks Lose Accuracy, Reduce Certainty
and âQualityâ of Knowledge!
36. Which Looks More Accurate?
Hamleyâs Queen Etharâs Lego Queen
OR
37. Small tasks, small batches, small cycles, small timescales, small change,
small planningâŚ
TAKEAWAY: KEEP STUFF SMALL!
39. ACTIVITY: Can it be Too Small?
Team A: 2 Dev + Product Owner
⢠8 sticks x 5 blocks each
⢠Each block is a task
⢠Each task
â Pull in stack
â Take 2 blocks from stack
â Place into ready
⢠Pay Per Delivery
Team B: 4 Dev + Product Owner
⢠8 sticks x 5 blocks each
⢠Each block is a task
⢠Each task
â Pull in stack
â Take 1 block from stack
â Place in ready
⢠Pay Per Delivery
Question: Who Wins? Why?
40. Beware Context Switching
⢠What are context
switches?
â Task Done that Doesnât
Add Value!
⢠The âZeroâ cost switchâŚ
â âŚDoesnât exist!
⢠Switching yourself
between tasksâŚ
⢠But what else?
Tasks Between Stages!!
â Columns, People,
BoardsâŚ
Total Replatforms
Large Business Pivots
Mass Change
Programmes
Entire Codebase Rewrite
âŚ
41. Small tasks, small batches, small cycles, small timescales, small change,
small planningâŚ
TAKEAWAY: KEEP STUFF SMALL!
(INCLUDING CONTEXT SWITCH COST)
42. Thanks for Watching
Links
Kanban Simulator
http://www.kanbansim.org/
Queuing Theory
http://en.wikipedia.org/wiki/Queueing_theory
Attribution
All images courtesy of Google images and are the property of their respective owners
Ethar Alali @EtharUK @Dynacognetics
Managing Director & Chief Architect
Polymath-MathMo. Programming since 9 years old. TOGAF 9 Certified, change
agent.
Blog: GoadingtheITGeek.blogspot.co.uk
About Me
Managing Director/CEO of Dynacognetics.
Specialist Agile-EA, ICT Strategist & Advisor.
Member of HiveMind Network.
Accredited Growth Voucher Advisor
certified to deliver IT & Web Growth
Consultancy to SMEs and Startups as part of
the governmentâs Growth Voucher Scheme.
Accreditations & Associations