Author
A step-by-step guide to measuring willingness to pay with the four Van Westendorp questions, with spreadsheet formulas and a worked example that finds the acceptable price range.
Sharpen it
A step-by-step customer discovery playbook: who to recruit, a 35-minute interview script built on past behaviour instead of opinions, how to take comparable notes, and a three-signal score that turns ten customer interviews into a decision.
Run the playbook
A retention curve that flattens is the clearest usage signal of product-market fit. How to build one with cohort analysis, a worked example with the formula, bounded versus unbounded retention, and how much data you need before you trust it.
See the numbers
A product-market fit case study of Superhuman: how one survey question, a narrower segment and a roadmap split in half took its very-disappointed score from 22% to 58%, and how to run the same numbers on your users.
Read the teardown