Frameworks for identifying, prioritizing, and testing product assumptions.
Riskiest Assumption Test (RAT)
## Assumption Map
### Desirability (Will they want it?)
| Assumption | Evidence For | Evidence Against | Risk Level |
|------------|--------------|------------------|------------|
| [Users want X] | [data] | [data] | High/Med/Low |
### Viability (Will it work for the business?)
| Assumption | Evidence For | Evidence Against | Risk Level |
|------------|--------------|------------------|------------|
| [Users will pay $X] | [data] | [data] | High/Med/Low |
Feasibility (Can we build it?)
| Assumption | Evidence For | Evidence Against | Risk Level |
|---|---|---|---|
| [We can integrate with X] | [data] | [data] | High/Med/Low |
Riskiest Assumption to Test Next
Assumption: [The one with highest risk + least evidence] Test: [Cheapest way to validate/invalidate] Success Criteria: [Specific threshold] Timeline: [Days/weeks]
## Product Hypothesis Format
```markdown
## Hypothesis: [Short name]
**We believe that** [building this feature/making this change]
**For** [target user segment]
**Will result in** [expected outcome/behavior change]
**We will know we're right when** [measurable success criteria]
### Riskiest Assumption
[The assumption that if wrong, invalidates the hypothesis]
### Minimum Test
[Cheapest/fastest way to validate]
- Type: [Prototype/Fake door/Concierge/etc]
- Duration: [X days/weeks]
- Sample size: [N users]
### Decision Criteria
- **Ship if:** [specific threshold met]
- **Iterate if:** [mixed signals, specify]
- **Kill if:** [specific threshold not met]
Test Types by Assumption
| Assumption Type | Test Method | Timeline |
|---|---|---|
| Desirability | Fake door, landing page | Days |
| Usability | Prototype testing | Days |
| Value | Concierge MVP | Weeks |
| Feasibility | Technical spike | Days |
| Viability | Pre-sales, LOIs | Weeks |
Assumption Prioritization
Priority = Risk Level × Impact if Wrong × Cost to Test (inverse)
Test assumptions that are:
- High risk (least evidence)
- High impact (invalidates entire concept)
- Low cost to test (quick experiments)