Years ago, I read a short crime story in a society that had a computer that could predict crimes.  One day it predicts that there will be two murders.  The police quickly start tracking where and who will be involved in the murders.  Meanwhile, a woman is directed to go to a certain room and push a button.  The police show up just after she completes her assignment.  It turns out, that the computer directed the woman to turn itself off – to “murder” the computer.  The dilemma is who do you blame for the “murder?”  The computer or the woman?  It was a one-off situation.

I was reminded of this story when I was asked the other day for material about a quality technique – mistake proofing to be specific.  While I have a lesson on mistake proofing, just giving it to someone is practically useless – there’s too much that is explained during discussion that’s not in the lesson slides.  That’s because mistake proofing is a concept, not a technique.  It’s the difference between internal combustion and the engine in a Shelby Mustang – understanding the concept doesn’t help you build or repair the engine unless you understand the system in which it is contained.  It’s a one-off.

That’s the lesson from the short story.  The woman didn’t understand what the button would do – she just pushed the button when told to do so.  So, it is when someone is taught a technique, a one-off, without understanding the context of system and consequences.  This is the heart of Deming’s profound knowledge:

  • Appreciation of a system
  • Theory of knowledge
  • The psychology of change
  • Knowledge about variation

Without this profound knowledge, you are only pushing buttons hoping that you’ll get good results.  Unfortunately, it’s a lot like playing the numbers on a roulette wheel – the odds are grossly against you.

The process of improving processes and systems is simple in concept and is summed up in the PDCA – Plan-Do-Check-Act – cycle.  But the application generates complexity because we rarely deal with “simple” processes – most processes require many inputs and steps – each which generates opportunities for accidents or mistakes – all sources of variation compounded by the performance of different individuals.

So, in answer to the request, I would say that mistake proofing is proper only after you understand the process, after you have simplified the process, after you have eliminated any waste – only then can mistake proofing be used to eliminate error and hence variation.  It is not a one-off.

Otherwise, you are just going through the motions with much of your effort being rendered useless because you will miss the diamonds and gold while sifting the dirt.  There’s nothing a demotivating as working hard only to discover that your work is in vain – the image of Cool Hand Luke digging holes comes to mind.  And that is what learning a technique – mistake proofing, in this case – without understanding it’s prerequisites, co-dependencies and consequences – will result in.

Therefore one-offs – the application of a specific technique or concept – rarely result in anything good.  We live in a world that is complex – both statically and dynamically.  And any time you ignore the complexity, you will end up with results that don’t match your expectations.

Which is why what you want to do is not going to work.

A physicist by trade, author by choice, a born teacher, a retired veteran, and an adamant problem solver, Frank has helped the White House, federal agencies, military offices, historical museums, manufacturers, and over 250 technology startups get stuff done, communicate effectively, and find practical solutions that work for them. In his spare time, he makes sawdust and watches Godzilla movies.