Are People Foolishly Incompetent? No, and Here's Why!

Posted on March 12, 2012 by


As a young engineer the first Shingo book I read was, “A Revolution in Manufacturing: The SMED System: Single-minute Exchange of Die System”. I then went on to read the others. His discovery and development of mistake-proofing in Zero Quality Control: Source Inspection and the Poka-Yoke System was as epiphany to me. Fresh out of college I obviously thought that narrowing tolerances would, of course, lead to an increased cost of manufacturing. Shingo taught me otherwise and was essential reading in my formative years with his active promotion of “Zero Quality Control” philosophy. He introduced me to the idea that inspection could be eliminated and you could have a reduced reliance on SPC. I was working in the “inspection department” in a large engineering firm, and looking back now, I guess these ideas were somewhat revolutionary at the time. The general consensus amongst the Senior Inspectors was the people were generally stupid and that was why they made mistakes, “foolishly incompetent” was a phrase that was thrown about a lot.

I saw experienced Operators; people who “should know better” (accoriding to the Inspectors) make mistakes. After time went on I understood that we could have the “best” inspectors, 100% inspecting all products and customers would still find problems and return some of them. It dawned on me that perhaps these inspectors themselves were making mistakes! So, it therefore made sense that Production Engineers should try to eliminate the potential for defects as opposed to finding the defects.

Shingo taught me that people will naturally be distracted by something or other and if the system they were working in let them then this would lead to the production of a defect. Shingos four principles still hold true:

  1. Control upstream, as close to the source of the potential defect as possible.
  2. Establish controls in relation to the severity of the problem.
  3. Think smart and small
  4. Don’t delay improvement by overanalysing.

Shingo was my first exposure to a true ‘systems thinker.’ Being able to visualise causes and effects, interactions and dynamic behaviours. As relevant now as he ever has has been.

Posted in: Lean