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| Criterion |  Decision Making Assumption Surfacing |  UX Research User Interviews |  Operations 8D Problem Solving |  Operations 5 Whys |
|---|---|---|---|---|
Purposedifferent | Plans often contain assumptions that were never openly stated and remain dangerous precisely because of that. Assumption Surfacing makes these silent premises visible and prioritizes which of them carry the initiative or could sink it. | When teams derive needs only from assumptions and real motives are missing, user interviews give direct access to behavior and meaning. Conversations from the target group's everyday life make patterns, tensions, and open questions solidly visible. | For an acute quality or delivery problem, the method structures immediate protection and root cause work together. It keeps the situation stable while the actual cause is investigated cleanly. | For a single, hard-to-explain deviation, the method exposes the causal chain behind the visible symptom. It keeps the cause open until a controllable condition emerges instead of a mere description. |
Complexitydifferent | Low | Low | High | Low |
Timedifferent | 45-90 min | 30–60 min per interview | 1-6 Wochen | 15-30 min |
Participantsdifferent | 2-8 | 1 participant per interview | 4-10 | 2-6 |
Formatdifferent | Workshop + async | Workshop + async | Workshop + async | Workshop |
Outputdifferent | Assumption List, Critical Assumptions, Learning Plan | Interview Notes, Themes, Insight Summary | 8D Report, Containment Plan, Root Cause Evidence, Corrective Action Plan | Root cause notes, Countermeasures |
Tagsno overlap | AssumptionsRiskDecisionDiscovery | QualitativeResearchCustomerDiscovery | QualityProblem solvingRoot cause | Root causeIncidentLeanProblem solving |