Structured Problem Solving

Structured Problem Solving

Framework

IRON LAW: MECE or It's Not Structured

Every decomposition must be MECE:
- Mutually Exclusive: No overlap between categories
- Collectively Exhaustive: No gaps — all possibilities covered

"Revenue = New customers + Existing customers" is MECE ✓
"Revenue = Online + Enterprise + Growth" is NOT MECE ✗ (overlapping)

Core Tools

Issue Tree: Decompose a question into sub-questions, MECE at each level

"Why is profit declining?"
├── Revenue declining?
│   ├── Volume down?
│   │   ├── New customer acquisition down?
│   │   └── Existing customer churn up?
│   └── Price down?
│       ├── Discounting increased?
│       └── Mix shift to lower-priced products?
└── Costs increasing?
    ├── COGS up?
    └── OpEx up?

Hypothesis-Driven Approach: Instead of exploring everything, state a hypothesis and test it

1. Form an initial hypothesis ("Profit declined because churn increased")
2. Identify what evidence would prove/disprove it
3. Gather that specific evidence
4. Refine or reject the hypothesis
5. Repeat

Pyramid Principle (Barbara Minto): Structure communication top-down