Retrospective Technique - 5 Whys
The 5 Whys is an iterative question-asking technique used to explore the cause-and-effect relationships underlying a particular problem.The primary goal of the technique is to determine the root cause of a defect or problem. (The "5" in the name derives from an empirical observation on the number of iterations typically required to resolve the problem.) A key phrase to keep in mind in any 5 Why exercise is "people do not fail, processes do". Source- 5 Whys Example- The vehicle will not start. (the problem) Why? - The battery is dead. (first why) Why? - The alternator is not functioning. (second why) Why? - The alternator belt has broken. (third why) Why? - The alternator belt was well beyond its useful service life and not replaced. (fourth why) Why? - The vehicle was not maintained according to the recommended service schedule. (fifth why, a root cause)