5 Whys

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3sets

5 Whys — Template

See past the first explanation. 20 minutes, 2 people.


Rules

  1. One person asks, one answers — clear roles.
  2. After each "Why?" quickly check: Does the answer describe a person or a system? Person = wrong turn. System = continue.
  3. Stop when the cause is outside the team's sphere of influence. Then the last answer becomes the escalation question.

Symptom

Write the observable symptom in one sentence:


The five whys

Five is a heuristic, not a law. Sometimes three is enough. Sometimes you need seven.


3sets interpretation

Which set is the cause (can be more than one)?

Set Finding ×
Tool-Set — tool, process, structure
Skill-Set — skill, experience, routine
Mind-Set — attitude, assumption, culture

Example

Symptom: "Our test automation delivers no value."

Why? Because tests often fail. Why? Because they're flaky. Why? Because test data and environments are unstable. Why? Because nobody owns the test infrastructure. Why? Because automation is treated as a side task.

3sets interpretation:

  • Tool-Set: Unstable test environment.
  • Skill-Set: Missing know-how for robust test architecture.
  • Mind-Set: Quality is not treated as a product.

Pitfalls


Source: The 3-Sets Method — Diagnostic Methods. More at 3sets.org/en.