It is the Operator’s Fault!

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Thanks so much for reading our publication. We hope you find it informative and useful. Happy charting and may the data always support your position.


Dr. Bill McNeese
BPI Consulting, LLC

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Comments (6)

  • Michael GamlenNovember 30, 2014 Reply

    Thanks for your excellent newsletter on this subject.  It is so clear to understand – and useful!

  • Allan PatersonJuly 27, 2015 Reply

    This remains one of my favourite articles of all time.My only disappointment is that you've modified the % increasing it from 6% to 6% to 15%, I've got my copy of the original article and Deming's texts and he only ever mentions 6%, i.e. 94% is "managements" fault.After 30 years in manufacturing I tend to agree with Dr Deming!!

    • billAugust 2, 2015 Reply

      Hi Allan,
      Thanks for the comments.  I agree that the percent if closer to 6% based on my experience as well – probably less.  I am trying to remember where the 15% came from.  It is the first number I remember hearing.  I attended a seminar by Dr. Deming back in the early 80s.   I do believe it started out at 15% – maybe not from Dr. Deming.  Dr. Deming has 6% in his Out of Crisis book.   I thought it might be in his book Quality, Producitivity and Competitive Position, but I do not see it in there.  You see 15% around a lot still.  Maybe it came from early training in SPC I received. 

  • ALCFebruary 17, 2018 Reply

    Your answer is wrong. The total number of efs in the sentence is 6. But you specify "F" as a capital letter – and there is only one of those. You needed to be more precise in the way you asked the question.

    • billJuly 1, 2019 Reply

      From your perspective, my answer is wrong.  Not from mine.  That is the reason you need good operational definitions.  Is a "f" an "f" or an "F"?  People often get blamed for making mistakes when the poor instructions  are too blame.  To me, it can be a "f" or an "F".  You comment about being more precise is exactly one point the article is making.  Dr. Deming called them operational definitions.

  • David M. LabarreNovember 20, 2018 Reply

    Very well illustrated post with all the facts explained with valid examples to make you understand the root cause of the problem.Actually mistake is so common for everyone and so this post is for every common person.

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