thinking-five-whys-plus

npx skills add majiayu000/claude-skill-registry --skill thinking-five-whys-plus --agent claude-code

Same command for any agent — swap --agent for codex, cursor, copilot.

# Five Whys Plus ## Overview The Five Whys technique from Toyota Production System is powerful but often misapplied. This enhanced version adds explicit guards against common failures: premature stopping, single-cause bias, blame-oriented thinking, and confirmation bias. It transforms a simple technique into a rigorous root cause methodology. **Core Principle:** Keep asking "why" until you reach actionable root causes, but guard against the technique's known failure modes. ## When to Use - Incident post-mortems - Bug investigations - Process failures - Customer complaints - Recurring problems - Any situation where you need root cause, not just proximate cause Decision flow: ``` Problem occurred? → Is the cause obvious and verified? → yes → Fix directly → Need to find root cause? → yes → APPLY FIVE WHYS PLUS → Is this a complex multi-factor problem? → yes → Consider Kepner-Tregoe PA ``` ## Standard Five Whys Failure Modes | Failure Mode | Description | Guard | |--------------|-------------|-------| | Premature stopping | Accepting first plausible cause | Minimum depth + actionability test | | Single-cause bias | Assuming one root cause | Branch on "what else?" | | Blame orientation