What Is the 5 Whys Technique? Key Terms 5 Whys A root cause analysis technique, developed within the Toyota Production System and attributed to Taiichi Ohno, that iteratively asks “Why?” five times (or as many times as necessary) to drill beneath surface-level symptoms to the underlying root cause of a problem. The premise: most problems … Continue reading 5 Whys Root Cause Analysis: How to Find and Fix Problems Permanently