Assumption mapper

Assumption Mapper

Every product bet rests on a stack of assumptions. This skill makes them explicit, classifies each as Known / Believed / Hoped, and produces a ranked test plan so the team validates the riskiest assumptions before committing to build.

Core Principle

The assumptions you don't write down are the ones that kill the product. Hidden assumptions become "obvious in hindsight" only because no one stress-tested them. The mapper's job is to drag them into the open and force a verdict on each.

The 3-Tier Classification

Tier	Definition	Action
Known	Direct evidence, multiple independent sources, recent data	No test needed; document the evidence link
Believed	Reasonable inference from indirect or partial evidence	Test if assumption is critical; defer if not
Hoped	Wishful thinking dressed as reasoning; no real evidence	Test before any meaningful investment

Cross with criticality (Critical / High / Medium / Low) → the Critical × Hoped quadrant is the team's actual risk surface.

Assumption Categories

The mapper walks through 5 categories to surface assumptions a one-shot brainstorm misses:

Category	Example Assumptions
Customer / Demand	"SMB ops leaders feel this pain weekly"; "buyers will pay $X"
Solution / Product	"Our approach is materially better than the workaround"; "the model can hit 90% accuracy on this task"
Channel / Distribution	"We can acquire this segment via content"; "our sales team can sell this without retraining"
Economic / Unit	"CAC stays under $X at this segment"; "support cost scales sublinearly"
Competitive / Time	"Incumbents won't ship this within 6 months"; "the platform shift continues for 2+ years"

Output

Save to outputs/assumption-map-[initiative]-[YYYY-MM-DD].md

• Assumption Inventory - every assumption surfaced, by category
• Classification Matrix - Known / Believed / Hoped × Critical / High / Medium / Low
• Risk Surface - the Critical × Hoped quadrant, called out explicitly
• Test Plan - for each Critical × (Hoped or Believed) assumption: smallest test that would invalidate it, expected duration, success criteria
• Defer List - Low-criticality assumptions that don't justify a test (named so they're not silently treated as Known)

Process

Step 1: Frame the Bet

I'll ask:

"Describe the initiative or strategy in 2-3 sentences. What does success look like 12 months from now?"

Step 2: Walk the 5 Categories

Surface 4-8 assumptions per category. Aim for uncomfortable assumptions - the ones the team would rather not name.

Step 3: Classify

For each assumption, classify Known / Believed / Hoped with the evidence (or absence thereof) noted.

Step 4: Rank by Criticality

Critical = the bet fails if this assumption is wrong. Most initiatives have 3-5 Critical assumptions; if the count is higher, the initiative is too entangled and should be decomposed.

Step 5: Build the Test Plan

For each Critical × (Hoped or Believed), design the smallest test that would invalidate the assumption. Tests are ranked by speed-to-disconfirm, not by speed-to-confirm.

Step 6: Pre-Mortem Pass

For each Critical × Hoped, write one sentence: "If this assumption is wrong, the initiative fails because…" If you can't write that sentence, the assumption isn't actually Critical.

Tips

1. Tests are designed to disconfirm, not confirm. Confirmation bias is the default; rigorous tests look for the cheapest way to be proven wrong.
2. Decompose entangled bets. An initiative with 8 Critical assumptions is really 3 initiatives stacked.
3. Re-map at major milestones. Yesterday's Known can become today's Believed when context shifts.
4. Hoped is not a slur. Most novel products start with several Hoped assumptions; the discipline is acknowledging them, not avoiding them.