1. Five Whys is a problem-solving method that encourages problem-solvers to explore beyond the most immediate apparent cause of a problem by asking what causes the apparent cause, what causes the secondary cause, etc, down to the 5th-level cause.


1. Sir Arthur Conan Doyle, Sign of the Four (New York: Penguin Classics, October 2001), pg 16.

2. Lean and Six Sigma techniques are classic Business Improvement or Continuous Improvement techniques. A Fishbone Diagram is a cause and effect diagram that structures efforts to identify different types of potential causes of a problem.

3. The PackCorp scientific process was an early Process Improvement method, developed by PackCorp for internal use. It expanded upon early methods ...

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