14. Kanban is a method for managing knowledge work with an emphasis on
just-in-time delivery while not overloading the team members.
In this approach, the process, from definition of a task to its delivery to the
customer, is displayed for participants to see and team members pull
work from a queue.
#softtechph
Source: Wikipedia
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15. Kanban can be divided into two parts:
#softtechph
Kanban system (small "k")
The Kanban method (capital "K")
Source: Wikipedia
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16. #softtechph
The word "kanban" (small "k") refers to (看板).
A "kanban system" (small "k") refers to a pull system implemented with
(virtual) . A visual process management system that tells
what to produce, when to produce it, and how much to produce.
The "Kanban Method" (capital "K") (as formulated by David J. Anderson) is an
approach to incremental, evolutionary process and systems change for
organizations. It uses a as the
core mechanism to expose system operation (or process) problems and
stimulate collaboration to continuously improve the system.
Source: Kanban: Successful Evoluoutionary Change for Your Technology Business by David J. Anderson
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17. To summarize, the Kanban method:
to continously improve the system.
#softtechph
uses a "pull" system,
limits work-in-process,
and exposes (or displays visually) the system operation (problems),
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18.
19. #softtechph
Why use a "pull" system?
Why limit WIP (Work-In-Process)?
Why expose the process for all participants to see? Why make it visible?
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21. #softtechph
Push System
Pull System
Resources are provided to the consumer based on forecasts or schedules.
Make all we can (just-in-case).
A method of controlling the flow of resources by replacing only what has
been consumed.
Make what's needed when we need it (just-in-time).
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24. If you are working on something exciting that
you really care about, you don't have to be
pushed. The vision pulls you.
“
”
Steve Jobs (1955 - 2011)
Apple
(emphasis added)
25. Little's Law:
L = average number of users in the system
λ = rate at which users arrive in the system
W = average waiting time that a user spends in the system
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26. Little's Law:
Let's say, at a store, customers arrive at a rate of 10 per hour, and...
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27. Little's Law:
Let's say, at a store, customers arrive at a rate of 10 per hour, and stay an
average of 0.5 hours.
Based on Little's Law, we should find that the average number of customers in
the store at any time to be...
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28. Little's Law:
Let's say, at a store, customers arrive at a rate of 10 per hour, and stay an
average of 0.5 hours.
Based on Little's Law, we should find that the average number of customers in
the store at any time to be 5.
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29. Little's Law:
L = average number of users in the system
λ = rate at which users arrive in the system
W = average waiting time that a user spends in the system
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30. Little's Law:
L = average number of users in the system (work-in-process)
λ = rate at which users arrive in the system (throughput)
W = average waiting time (or cycle time) that a user spends in the system
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38. To improve cycle time, only two options are available:
#softtechph
Increase throughput
Reduce WIP
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39. What does WIP reduction have to do with software development?
There is causation between quantity of WIP
and average lead time (or cycle time), and the
relationship is linear.
“
”
David J. Anderson, p. 27,
Kanban: Successful Evoluoutionary Change for Your Technology Business
40. Longer lead times seem to be associated with
significantly poorer quality.
“
”
David J. Anderson, p. 27,
Kanban: Successful Evoluoutionary Change for Your Technology Business
41. In fact, an approximately six-and-a-half times
increase in average lead time resulted in a
greater than 30-fold increase in initial defects.
“
”
David J. Anderson, p. 27,
Kanban: Successful Evoluoutionary Change for Your Technology Business
42. However, at the time of writing there is no
scientific evidence to back up this empirically
observed result.
“
”
David J. Anderson, p. 28,
Kanban: Successful Evoluoutionary Change for Your Technology Business
61. To summarize, the Kanban method works because:
to continously improve the system.
#softtechph
it uses a "pull" system,
limits work-in-process,
and exposes (or displays visually) the system operation (problems)
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