What is ‘Poka-yoke’?
Poka-yoke can be best translated as ‘Fail Safe’; It can not go wrong/be done wrong
Poka-yoke can be a mistake-proofing device or procedure to prevent making a mistake.
Fail-safe by design
Poka yoke can also be a design-choice: It is not possible to put a 9 volt battery in a 1,5 volt device. Or a 220 volt plug in a 380 volt outlet. The design makes such mistakes impossible: Fail Safe!
In factories we see levers or light beams along an assembly line that is tripped to prevent people reaching into the running machine.
Poka-yoke measures are important provisions in zero defect producing environments. In such an environment, in worst case the process stops (Jidoka), but (in the ideal situation) it is not possible to produce a defect product.