Root Cause Analysis.
WS02 goes beneath the surface of WS01 Situation Statement to find the actual cause — using the 5 Whys technique, with an optional Fishbone (Ishikawa) diagram for situations with multiple contributing causes.
Purpose
The situation statement describes symptoms. WS02 isolates the root cause, so the plan doesn't target the wrong thing. A program that skips WS02 tends to produce solutions that address the visible part of the problem while leaving the real driver untouched — then re-surfaces in hypercare.
When to use
Immediately after WS01 is finalized, in the Situation phase. Both WS01 and WS02 must be signed off before moving into Assess; the root cause is what the solution options in WS05 will ultimately have to address.
Template: 5 Whys
- Restate the "Currently…" line from WS01.
- Why is this happening? (Answer 1 — evidence-based)
- Why is Answer 1 true? (Answer 2)
- Why is Answer 2 true? (Answer 3)
- Why is Answer 3 true? (Answer 4)
- Why is Answer 4 true? (Answer 5 — usually the root)
Stop when the next why would lead to "that's just how the system works" — that's the actionable root.
Optional: Fishbone
For situations with multiple contributing causes, the fishbone diagram groups causes into categories (common sets: People, Process, Technology, Environment; or the 6Ms: Manpower, Method, Machine, Material, Measurement, Milieu). Each category gets its own "why" branch. Useful for complex operational issues where a single 5-Whys line misses contributing factors.
Validation
Test the candidate root cause: "If we fixed this and only this, would the situation in WS01 go away?" If yes, you've found the root. If no, you stopped early — keep asking why, or switch to a fishbone.