Jidoka — often translated “automation with a human touch” — is the principle that processes stop themselves at deviations, so defects are never passed on. Jidoka is the second pillar of the Toyota Production System alongside Just-in-Time.
The sequence is: detect the deviation, stop, fix immediately, find the root cause and build in the countermeasure. The stop element is counterintuitive — stopping costs output — but it forces the organisation to solve problems instead of living with them.
Jidoka also decouples people from machines: when the machine stops itself on error, no one needs to stand and watch it, and one operator can run several machines.