Taiichi Ohno
Anyone may pull the cord
The problem surfaces where it happens
Taiichi Ohno, Toyota Production System; Sakichi Toyoda's self-stopping loom
What you hand out comes back wrong every time. Why Toyota let any worker on the line halt the entire line.
What actually happened?
Toyota began as a loom maker. Sakichi Toyoda's loom had one design feature: when a thread broke the machine stopped itself, instead of weaving out a whole bolt of ruined cloth. Ohno moved the idea onto the car line. A cord hangs above every station, and anyone who sees a problem can pull it and stop the whole line. Management feared the lost output. He held. The result is that a fault surfaces in the second it occurs and is handled there, rather than accumulating into a pile of scrap found at the month-end count.
The earlier a defect stops, the cheaper it is
An error caught at the first station costs a minute. The same error found at the last one costs the whole unit. Work that comes back to you wrong every time is telling you there was no point along the way where anyone could halt it.
If there is no checkpoint between handing the work out and getting it back, what comes back will be wrong.
Give the power to stop to the people furthest down
Whoever sees the problem first is on the line, not in the office. If only a manager may stop, the problem has to travel upward and wait for permission, and by then it has flowed past. Give the stop to whoever can see, and it stops where it started.
Letting the person doing the work say wait, this is not right is worth ten times any inspection you run afterwards.
Fear of stopping the line manufactures defects
The instinct of management is to keep running, because output matters. But what keeps running is defective output, and more of it is worse. His ordering is the reverse of the instinct: stopping is what produces, and refusing to stop is what really cuts production.
Get it out now and fix it later mostly produces rework, and rework costs far more than the pause would have.
How do I use it today?
Where you are: what you hand out comes back looking nothing like what you asked for, and you send it back every time.
Ask first: between handing this out and receiving it, how many points are there where somebody could call a halt? When the person doing the work sees something wrong, may they stop, and do they dare?
Where it goes wrong: reading it as everything must be escalated. The cord is pulled on an abnormality, not on the normal flow. And it is not a licence to watch people harder — the power moves down, not up.
Lines to keep
A thread breaks, the loom stops, and nothing ruined is woven.
Give the power to stop to whoever can see the problem.
Stopping is what produces. Refusing to stop is what cuts output.
Same situation, other people are asking
I explained it and what came back was not it.Everything is orderly now and we've somehow got slower.What I ask for and what I get are never the same thing.We added people and less gets finished than before.Nothing ships · all 12 questions →If this one named what you are going through,
send it to someone who needs it, or keep it somewhere you will find it again.