[lkuk13] i broke the wip limit twice, and i'm still on the team

@ZsoltFabokhttp://zsoltfabok.com/

#lkuk13http://lkuk.leankanban.com/

byZsolt Fabok2013.11.01

Broke the WIP limit TWICE

Still on the team

http://zsoltfabok.com/

http://zsoltfabok.com/

@ZsoltFabokand /or

#lkuk13

lead time(minutes)

moving (minutes)

waiting (minutes)

flow efficiency

46 40 6 87%

44 40 4 91%

35 31 4 89%

38 26 12 68%

The time I need to get to work by bicycle

Where is the Kanban Method in all this?

It is in the deltas between the steps; the desire to improve continuously.

Small incremental evolutionary changes(continuous improvement)

The Pull System

If you understand the purpose of small incremental evolutionary changes and the pull system, you’ll do fine with the Kanban

Method, because you can easily deduce the rest.

It is hard to improve the invisible, so we have to see what we have at our

hands.

Meet the team

Value Stream Mapping

Start with what you do now(possibly end to end)

Design

Implementation

Delivery

Test information

work item

Design

Implementation

Delivery

Test

Ready Design Implementation Test Delivery Live

This board was a “traditional” board, how about a less “traditional” one?

Courtesy of Prezi.com

We decided that we are going to discover our value stream (flow) on the go.


Flow (Stream)

The flow ([value] stream) starts at the left side, and ends at the right side of the board.

The Flow is different in a typical enterprise and start-up environment.

Typical enterprise flow

Flow (Stream)

Typical start-up flow

Flow

Flow

Flow

Now we can see the previously unseen, but we need to start pulling work items

otherwise they won’t get delivered.


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The pull system itself does not guarantee that work items get to be delivered.

That’s when the Work In Progress (WIP) limit comes into the picture.


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1 2 1 3

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How to set the WIP limit at the beginning?

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work done

staff liquidity + internal queue

Too low WIP limit creates unnecessary bottleneck, too high WIP limit encourages

multitasking and/or longer lead time.

Yes, the WIP limit can change over time.

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work done

week 1 week 2 week 3 week 4

Car manufacturingvs

software engineering

“The inventory”

“Too many workers, equipment, and product only increase the cost and cause secondary waste. For example, with too many workers, unnecessary work is invented which, in turn, increases power and materials usage. This is secondary waste. The greatest waste of all is excess inventory. If there is too much inventory for the plant to store, we must build a warehouse, hire workers to carry the goods to this warehouse, and probably buy a carrying cart for each worker.”

“In the warehouse, people would be needed for rust prevention and inventory management. Even then, some stored goods still rust and suffer damage. Because of this, additional workers will be needed to repair the goods before removal from the warehouse for use. Once stored in the warehouse, the goods must be inventoried regularly. This requires additional workers. When the situation reaches a certain level, some people consider buying computers for inventory control.”

“Too many workers, equipment, and product only increase the cost and cause secondary waste. For example, with too many workers, unnecessary work is invented which, in turn, increases power and materials usage. This is secondary waste. The greatest waste of all is excess inventory. If there is too much inventory for the plant to store, we must build a warehouse, hire workers to carry the goods to this warehouse, and probably buy a carrying cart for each worker.”

“In the warehouse, people would be needed for rust prevention and inventory management. Even then, some stored goods still rust and suffer damage. Because of this, additional workers will be needed to repair the goods before removal from the warehouse for use. Once stored in the warehouse, the goods must be inventoried regularly. This requires additional workers. When the situation reaches a certain level, some people consider buying computers for inventory control.”

“...The greatest waste of all is excess inventory. If there is too much inventory for the plant to store, we must build a warehouse...”

Car manufacturingvs


“The inventory”

(At Toyota the inventory is finite, however in software engineering it is infinite, therefore we cannot approach it with the same attitude)

And now, back to the queues.

There is another kind of queue: the infinite queue.

21

Visible

Invisible

2 3

Infinite queues

Now the work items are getting delivered, it is time to improve the system.

Improvement requires measurement.

The lead time

Ready Design Implementation Test Delivery Live1 2 1 3

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commitment

Distribution of lead times

days

count

0

3

5

8

10

13

15

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 22 28 33 56

average

median* *Calculation of medians is a popular technique in summary statistics and 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 than is the mean. Wikipedia

Courtesy of Digital Natives

Car manufacturingvs


“The takt time”

(In software engineering the demand is not quantitive, therefore it doesn’t matter how

much time we spend between two features)

Car manufacturingvs


“The throughput”

(In software engineering we don’t have to deliver 10 features, we have to deliver THE feature, therefore

the number of delivered feature doesn’t help us, but it is a good “secondary” measure to see how we react

to changes, or how good we are at forecasting)

0

2

4

5

7

week 1 week 2 week 3 week 4

incomingoutgoing

The throughput

The throughput (output) is helpful, if and only if it is compared to the

demand (input).

1 2 1 3

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0

2

4

5

7

w 1 w 2 w 3 w 4

6

The goal is to have a stable system (first target) because improvement on a stable system will have a long term

effect (second target).

1 2 1 3

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0

2

4

5

7

w 1 w 2 w 3 w 4

7

It is Monday on Week 5...

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Aging item

The aging items mess up your forecasting.

0

2

4

5

7

w 1 w 2 w 3 w 4

throughput

“We get N items a week” “We deliver N items a week”

“Therefore we can deliver an item in a week”

*This argument is so weak that a decent philosopher stops thinking about philosophy and looks for another profession every time one reads it up

“We deliver an item in a week”

Therefore our lead time is the length of the week which is 5 days)”*

days

count

0

3

5

8

10

13

15

1 2 3 4 5 6 7 8 9

But in reality you are actually here:

5 != [6,9]

Protect the bottleneck and don’t punish the phase before the bottleneck.

(with Theory of Constraints)

3 3 4 2

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Bottleneck

3 3 4 2

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It hurts here...

...because the work items queue up here.

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3 3 4

2

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2

Now the bottleneck is better protected...

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...and the phase before the bottleneck doesn’t suffer.

If you understand the purpose of small incremental evolutionary changes and the pull system, you’ll do fine in Kanban land,

because you can easily deduce the rest.

And be skeptical about the practices that come from the manufacturing world (context matters).

Thank you very much for your attention!

@ZsoltFabokhttp://zsoltfabok.com/

http://zsoltfabok.com

http://zsoltfabok.com

[lkuk13] i broke the wip limit twice, and i'm still on the team

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