This is a principle in the Toyota Production System as well-- in performing any problem analysis, you are to ask "Why?" 5 times to get to the root cause of the

This is a principle in the Toyota Production System as well-- in performing any problem analysis, you are to ask "Why?" 5 times to get to the root cause of the issue you are facing. If you want to get more structured about it, you can do a fishbone/ishikawa diagram, where there are specific categories of "why"s to check against: http://en.wikipedia.org/wiki/Ishikawa_diagram http://en.wikipedia.org/wiki/Ishikawa_diagram