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A Product Discovery Deck · 2026

Finding Product-Market Fit

A 90-day discipline for early-stage product teams.

Chapter 01

Why most discovery work doesn't stick

Chapter 01 · The problem

Discovery is collected, not practiced

Every team collects customer signals — interviews, tickets, churn calls. Most treat them as confirmation, not as falsifiable input.

Three failure modes

  • Signals are catalogued but never restated as hypotheses.
  • Tests are run to validate, not to falsify.
  • Negative results are quietly discarded.

Median across 200 teams

63%

of "discovery interviews" end without a written, falsifiable hypothesis.

Chapter 02

The Validation Loop

Chapter 02 · The Validation Loop

Restate the signal as a hypothesis

A signal is observation; a hypothesis is a prediction with a fail condition.

Exercise Pick last week's loudest signal. Rewrite it as one sentence containing a metric, a magnitude, and a timeframe.

Chapter 02 · The Validation Loop

Picking the right validation method

If you're testing… Use Why
Whether the problem is real and frequent Discovery interview Surfaces unprompted language and workarounds
Willingness to pay or commit Pre-sale / LOI Behavior is the only honest signal; opinions inflate
Whether a specific solution is usable Prototype test Concrete artifact; reveals where assumptions break
A discovery cycle that produces no killed hypotheses isn't validating — it's rationalizing the roadmap you already have.

— Notebook, week 4

End · Thank you

Ship one killed hypothesis per week.

That's the whole practice.

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