The sixth iteration of this talk, presented at Lean Kanban France 2012 (the previous iteration was presented at Lean Agile Scotland 2012)

1. Measure and Manage Flow in Practice
by
Zsolt Fabok
2012.10.18
Broke the WIP limit TWICE
Still on the team
@ZsoltFabok #lkfr12
http://zsoltfabok.com/ http://lkfr.org/

2. 5 Stories from the life of a team by using
real application and data
The collected data is the courtesy of Digital Natives

3. #1 Too many open items

4. Visualize the situation with
Cumulative Flow Diagram
WIP
point of observation solved

5. It offers more than just the WIP...
number of work items
The Cumulative Flow Diagram
Done
Started
Queued backlog
WIP
cycle time
lead time
time

6. The simplest way of collecting data:
Q 3 4 1 2 D
~ ~ ~ ~ ~ ~
~ ~ ~ ~ ~ ~
~ ~ ~ ~
~ ~ ~ ~
~ ~
~ ~
~
~

7. A quick detour:
CFD doesn’t say too much about
the throughput

8. /* detour */
work item
WIP
lead time
time

9. 2
/* detour */
work item
WIP
lead time
throughput

10. 2 2
/* detour */
work item

11. /* detour */
Let’s add more people to the
project so that “things speed up”!

12. 2 2 3
/* detour */
work item
coordination + communication cost

13. Actually, “things slow down”, so it
was not a good idea (solve the right
problem instead - systems thinking).
End of the detour.

14. #2 It takes too much
time to deliver

15. lead time

16. CFD was not much help here...
lead time
...because we didn’t know much about
the nature of the lead time

17. Distribution of lead times
count
15
13
10
8
5
3
0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 22 28 33 56
days
average
*Calculation of medians is a popular technique in summary statistics and
median* summarizing statistical data, since it is simple to understand and easy to calculate,
while also giving a measure that is more robust in the presence of outlier values

18. Some examples of work items with 8-day
lead time
time spent on time spent waiting
implementation (hours) %
(hours)
1 63 98
7 57 90
2 62 97
2 62 97
3 61 96

20. 95%
of the lead
time was spent
on waiting

21. Distribution of lead times
Before After
count count
15 15
13 13
10 10
8 8
5 5
3 3
0 0
days 1 4 7 10 13 16 33 days 1 3 5 7 9 11 13 22
average
median

22. #3 Still too many open
work items

23. How many
times the item
has been
rejected

24. Number of rejected work items
count
15
11
8
4
0
week 31-32 33-34 35-36 37-38

25. Number of rejected work items
count
15
11
8
4
0
week 31-32 33-34 35-36 37-38 39-40 42-43 44-45

26. #4 Being predictable

27. Sales: “I want to know when the
new features can hit the market!”
Management: “I want to know
how much it will cost me!”

28. All the work items we had so far
(~20 work items)
v
~ v ~
~ ~ v ~
v ~
v
~
v v
~ ~
~ ~
~
v

29. Categorizing them into three groups
S
v
~
~
v
~
~
~
M
~ ~
~ v
v ~
~
v
v
L
~
v
~
v

30. The lead time distribution
count
4
3
3
~
~
~
2
M
~ ~
~ v
v ~
~
v
v
1
1
0
days 1 2 3 4 5 6 7 8 9 12 13 16

31. The lead time distribution
count
4
3
3
~
~
~
2
M
~ ~
~ v
v ~
~
v
v
1
1
0
days 1 2 3 4 5 6 7 8 9 12 13 16
SLA

32. The lead time distribution
count
4
3
3
Ex
~
~
pi
~
2
M
~ ~
~ v
re
v ~
~
v
v
1
d
1
0
days 1 2 3 4 5 6 7 8 9 12 13 16
SLA

33. The spent time distribution
count
6
5
4
~
~
~
3
M
~ ~
~ v
v ~
~
v
v
2
1
0
hours 6 7 8 9 10

34. The spent time distribution
count
6
5
4
~
~
~
3
M
~ ~
~ v
v ~
~
v
v
2
1
0
hours 6 7 8 9 10
SLA

36. #5 Forced improvement

37. #2 Nothing changed.
Still the same ratio
#1 We decided that we would
force ourselves to keep the SLA

38. Evolution of the
team’s workflow

42. Final thoughts on
measurements

43. “If you can not measure it,
you can not improve it.”
Lord Kelvin
http://en.wikipedia.org/wiki/File:Lord_Kelvin_photograph.jpg

44. “If you start measuring
something you start
optimizing it, and I know it's
the wrong thing to optimize.”
Paul Graham
http://paulgraham.com/swan.html

45. The Hawthorne effect
might influence your
measurements

46. The key ideas

47. 1. We develop software not models (value)
2. Demand first, supply second
3. Observe the system (lead time, throughput)
4. Start measuring, look back if necessary
5. Manage
6. Mind that data expires
7. Goto step 3.

48. Thank you very much for your attention!
http://zsoltfabok.com/ @ZsoltFabok