What makes a good user interview, and what are some common mistakes PMs make when interviewing users?

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Accepted Answer

A good user interview is a structured conversation designed to uncover user needs, behaviors, and pain points without leading the participant toward a predetermined answer. It is one of the most valuable tools a product manager has for building empathy and making informed decisions.

The best interviews focus on past behavior rather than hypothetical futures. Instead of asking "would you use a feature that does X," ask "tell me about the last time you tried to accomplish X. What happened?" People are poor predictors of their own future behavior, but they can accurately describe what they have already done. This technique, drawn from the "Mom Test" methodology, helps you get honest signal rather than polite encouragement.

Preparation is essential. Before the interview, define your research questions: what do you need to learn and why? Create a discussion guide with open-ended questions organized by theme, but be prepared to deviate when the participant says something unexpected. The best insights often come from following tangents rather than sticking rigidly to your script.

During the interview, listen more than you talk. A good rule of thumb is the 80/20 ratio: the participant should be speaking 80 percent of the time. Use follow-up questions like "can you tell me more about that?" or "why do you think that happened?" to dig deeper. Avoid nodding enthusiastically or saying "great idea" because that signals approval and biases future responses.

Common mistakes include asking leading questions like "don't you think the checkout flow is confusing?" which suggests the answer you want. Another mistake is pitching your product during the interview instead of listening. A third mistake is only interviewing power users or fans, which gives you a biased view of your product.

After the interview, write up your notes immediately while the conversation is fresh. Identify patterns across multiple interviews rather than acting on a single conversation. Look for recurring pain points, workarounds that users have built, and emotional language that signals strong feelings about a problem.

A single interview is an anecdote. Five to eight interviews on the same topic typically reveal the major patterns and give you enough confidence to act.