The Mom Test: interviews that don’t lie

Why customer interviews lie to you

You found your riskiest assumption. Now you go ask people about it — and almost everyone does it wrong. They describe their idea, the other person is kind, says “great idea, I’d totally use that,” and the founder walks away with false confidence instead of truth. The problem isn’t the customer. It’s the questions.

The fix has a name — The Mom Test (Rob Fitzpatrick): ask questions so grounded in fact that even your mum couldn’t lie to you to make you feel good. Three rules make it work.

1 · Talk about their life, not your idea

The moment you describe what you’re building, the conversation is poisoned — they switch into cheerleading or critiquing your idea instead of telling you about themselves. Don’t pitch. You’re a curious stranger asking how their world works.

2 · Ask about the specific past, not the generic future

“Would you use this?” and “Do you usually…” invite fiction — people are optimists about their imagined future selves. Ask what actually happened: “Talk me through the last time this came up”, “what did you do?”, “what did it cost you?” Past behaviour is evidence; hypothetical future behaviour is a wish.

3 · Listen for commitment, not compliments

“I love it” is a compliment — it costs nothing and means nothing. Real signal is when someone gives up something they value: time (a follow-up, an intro), reputation (introducing you to their boss), or money (a deposit, a pre-order). If the problem is real, they’ve already tried to solve it and spent something. Find out what.