The Mom Test review

The Mom Test is Rob Fitzpatrick's short guide to customer development interviews — the conversations founders and product teams have with potential customers before building something. The central problem it addresses is that most of these conversations are useless, and the people having them usually don't realize it. The issue isn't dishonesty. It's politeness. People don't want to hurt your feelings. They'll say your idea sounds interesting, that they'd probably buy it, that they'd definitely recommend it to a friend. None of that means anything. Fitzpatrick's fix is a simple rule set for asking questions that customers can't lie about even if they want to, because the questions aren't about your idea at all.

The book's title comes from a test case: could your mom give you a useful interview if she loved you too much to criticize you? The answer is yes, if you ask the right questions. Good questions are about their life, not your idea. They ask about concrete past behavior rather than hypothetical future intentions. "How do you currently handle this problem?" is a good question. "Would you use something like this?" is not. "How much did that cost you last time it happened?" is good. "Do you think that's a common problem in your industry?" is not. The distinction sounds obvious stated plainly, but Fitzpatrick shows with repeated examples how consistently founders violate it — usually because they're unconsciously fishing for validation rather than information. The chapter walking through bad question after bad question is the most useful part of the book, because the examples are uncomfortably recognizable.