Kanban: from Toyota Corporation to Software Development

Kanban: from Toyota Corporation to Software Development


This is a Kanban board How many Kanban cards do you see? Keep that number in mind. Hi this is Gary. Welcome to Development That
Pays As you may know Kanban originated in the world
of manufacturing. Here’s a machine for processing… err…
Things! Thinks arrive from the left, are processed
through the machine And then move off to the right. So far so good. But what if things arrive at a greater rate? Slowly but surely things start to back up
to the left of the machine. This build up is a problem. There’s more work
in progress that there needs to be. And that represents a cost to the business
in a couple of ways: – There’s money tied up in each of these Things
– The Things are taking up floor space… which also has to be paid for. This is the problem that Mr. Taiichi Ohno
of Toyota set out to solve. He borrowed a trick that he spotted in an
american supermarket. Mr Ohno observed that store shelves were stocked
with just enough product to meet consumer demand. The inventory would only be restocked when
there was a visual signal – in this case, an empty space on the shelf. To transfer this to the factory, he needed
a way for one process to “ask” the PREVIOUS process for more stock. Enter, you guessed it, the Kanban card. Our machine processes a thing… and despatches a Kanban card to the previous
process. Kanban roughly translates as signboard or
billboard. The Kanban card is a signal to the previous
process to send a Thing along. Naturally, what’s good for the goose is good
for the gander. Our original machine is subject to the same
rule: It should only be processing in response to
demand. Meaning… another Kanban card. As thing stand, the work in progress is just
about as low as it can be… … but it’s also slower than it might be. We can speed things up by allowing a – strictly
limited – bit of Work In Progress. Notice that the additional things are held
to the right of the process that’s just processed it. That’s important, because it means that each
process is in control of its own Work In Progress. If we now think about a Kanban Board as used in Software Development The processes… are columns The Things… are the tickets The Kanban cards are… nowhere to be seen! Have we thrown the baby out with the bathwater? Not quite. The Kanban cards are with us in spirit if
not in body The important part about the Kanban SYSTEM
is the signalling. This column signals its need for a ticket
by virtue of its… err… emptiness. Much like the empty space of the supermarket
shelf. Talk to you next time.

About the Author: Michael Flood

2 Comments

  1. You are a great teacher. I've just watched a few of your videos. Love your style and succinctness. just great.

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