F****ing Estimates

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People are bad estimators. We all know it and still customers ask "when will it be done".

This talk lists a dozen explanations why estimating doesn't work and how potentially we can solve the more global problem of needing them.

F****ing Estimates

  1. 1. what’s the problem?
  2. 2. Denver Intl. Airport
  3. 3. Denver Intl. Airport
  4. 4. Eurofighter Typhoon
  5. 5. Eurofighter Typhoon
  6. 6. Sydney Opera House
  7. 7. Sydney Opera House
  8. 8. Vicious Cycle in IT BUSINESS WANTS A LOT WE GIVEBUSINESS STARTS UNREALISTIC TO PRESS ESTIMATES IT WE FAIL TO BECOMES EVEN DELIVER HARDER TO DELIVER
  9. 9. Let’s run an experiment!
  10. 10. A simple task + = $1,10The bat costs $1,00 more than the ball.How much does the ball cost?
  11. 11. Planning Fallacyhttp://en.wikipedia.org/wiki/Planning_fallacy
  12. 12. wishfulthinking optimism bias Planning Fallacy
  13. 13. Student were asked to assign probabilities of completion time 50% 75% 99 % 1.Nov 20.Nov 10.Dec
  14. 14. what would you think?
  15. 15. real completion rate14% 19% 45 % 50% 75% 99 % 1.Nov 20.Nov 10.Dec
  16. 16. Estimating time in real life
  17. 17. wishful thinking optimism bias Planning Fallacystudent’ssyndrome procrastination
  18. 18. wishful thinking optimism biasperfectionism Planning Fallacy procrastination student syndrome
  19. 19. “Anything less than perfect is unacceptable”“Work takes as much time as you have” Parkinson’s Law
  20. 20. gps paradox optimism bias wishful thinkingperfectionism Planning Fallacystudent syndrome procrastination
  21. 21. gps paradox wishful thinking optimism bias perfectionism Planning Fallacystudent syndrome procrastination delay propagation
  22. 22. E. Goldratt Delays get accumulated.Early completions get lost.
  23. 23. gps paradox wishful thinking optimism biasperfectionism Planning Fallacy student syndrome procrastination delay propagation
  24. 24. 4x 3x 2x 1.5xtime
  25. 25. what to do?
  26. 26. ONE MORE TIME1. Create …2. Never …3. … size …4. Measure …5. … = … /…6. …. customers7. Incrementally …

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