Building quality into the process, aka Jidoka, is a cornerstone of the Toyota Production System.
And embedded tests are a cornerstone of Jidoka.
To make a good product, or provide a good service, I need:
- A clear picture of what good is (i.e. a Standard)
- Quick feedback on how I'm doing right now, and
- A way of getting back to a good condition
Embedded tests address element 2, and should be
- Low cost, and
- Binary (i.e. OK/Not OK)
What's the best source of embedded tests?
Wait for it...front-line team members.
Who knows the work better?
Who else has absorbed the 'nicks & knacks of the work'?
That's why Total Involvement, and a profound respect for people are, the heart of the Lean Business System.
Without it, the system is akin to the Tin Man in the Wizard of Oz.
Efficient perhaps, but lacking the most important thing, a heart.
More on Jidoka next time.