Start with the decision, not the interview script
Customer interviews can serve very different purposes. Before inviting participants or writing questions, identify the decision you need to make. Are you trying to understand an unfamiliar problem, or do you have a particular concept, service, or experience to assess? That distinction points toward an exploratory or an evaluative interview.
Exploratory interviews are useful when the team does not yet know enough about customers’ routines, priorities, or obstacles. Evaluative interviews are useful when there is something concrete to react to, such as a proposed feature, a message, a prototype, or an existing process. Neither approach is inherently better. The useful one is the one that matches the uncertainty behind your decision.
Use exploratory interviews to understand the customer’s world
An exploratory interview begins with the participant’s experience rather than your proposed answer. Its aim is to learn how people describe a situation in their own words: what triggers a need, what they do today, where they encounter friction, and what a satisfactory outcome would look like. This is especially helpful early in a project, when a team may be relying on assumptions about why customers behave as they do.
Ask for specific past examples instead of only hypothetical opinions. “Tell me about the last time you had to compare these options” is likely to reveal more about a process than “Would you use a comparison tool?” Follow up with neutral prompts such as “What happened next?” or “How did you decide?” Leave room for unexpected topics, even if they do not fit your initial outline.
Exploration should not become an unstructured conversation with no purpose. Choose a few topics tied to the decision at hand, recruit people who have relevant experience, and use a flexible guide to cover the same broad ground across interviews. Afterwards, look for recurring situations and meaningful differences, not just memorable remarks.
Use evaluative interviews to assess something specific
An evaluative interview puts a defined idea or experience in front of a participant. You might ask someone to examine a product page, walk through a prototype, or respond to a proposed service description. The goal is to learn how they interpret it, what helps or hinders them, and whether it addresses the need you intended to address.
Make the object of evaluation and the task clear, but avoid explaining what the participant is supposed to think. For example, ask, “What would you do next on this page?” rather than “Is the sign-up button easy to find?” Observe what the person does or notices before asking for an overall opinion. If they struggle, a follow-up question can help you understand their expectation without supplying an answer.
Reactions need context. A participant may like an idea in conversation but have little reason to use it in everyday life. Ask when they would encounter it, what they would compare it with, and what might stop them from acting. Treat stated preferences as clues to investigate, not as a reliable prediction of future behavior.
Choose the approach that matches your uncertainty
If your question is “What problem should we focus on?” start with exploration. If it is “Does this proposed solution make sense to the people it is for?” evaluation is a closer fit. When you need both, consider separate rounds: learn about the situation first, develop an idea, then return to participants with something to assess. This helps prevent an early concept from narrowing the conversation before you understand the problem.
You can include a small evaluative component in an exploratory session, but keep the boundary visible. Introduce the concept after discussing the participant’s existing experience, and note which observations came before and after they saw it. Otherwise, their responses to your idea may be mistaken for evidence that they independently identified the same need.
Recruitment matters in either approach. Select participants according to the experience relevant to your question, rather than treating any available customer as interchangeable. Someone familiar with the problem may be well suited to exploration; someone who would realistically encounter the proposed experience may be well suited to evaluation.
Turn interviews into a practical next step
Soon after each interview, record what the participant described, what you observed, and what you inferred. Keeping those separate makes it easier to revisit an interpretation later. Compare interviews by topic: situations, workarounds, points of confusion, unmet expectations, and notable exceptions. Avoid presenting a handful of interviews as a measure of how common a view is across an entire market.
End with a decision-oriented summary. Exploratory work might identify a problem worth investigating further or reveal that different customer groups have different priorities. Evaluative work might show where a concept needs clearer language, a different flow, or another test. State what remains uncertain as well as what you learned. A useful interview does not have to settle every question; it should make the next question or decision clearer.
