When you hear something interesting, follow up. "Tell me more about that" and "Can you give me an example?" are the most powerful prompts in customer research. They unlock detail without leading the witness.
Resist the urge to fill silence. When someone finishes answering, pause for a moment. Often they will keep talking and share something more revealing. The real insight is usually in the second thing they say, not the first.
Do not lead the witness. Saying "So you found the onboarding confusing, right?" puts words in their mouth. Instead say "How would you describe the onboarding experience?" Let them choose the words.
For a jewellery company that sold both in retail stores and online, we noticed they sold far more rings offline than online. The data was clear, but we did not understand why.
Customer interviews revealed the problem. The ring sizing guide was a five-page PDF from the factory, designed for B2B wholesale buyers. It was technical and confusing. Most website traffic was mobile, and nobody opens a five-page PDF while shopping on their phone. In the store, staff could measure your finger in seconds.
Once we knew the problem, the fix was obvious. But without talking to customers, we would have kept guessing.
I once interviewed customers for a coffee retailer who were buying beans all year round, then suddenly switching to coffee pads every summer. The pattern looked like a data error. Some kind of tracking bug.
When I called them, I discovered these customers had boats, camper vans, or holiday homes. In summer, they wanted the same brand but needed a different format for their portable espresso machine. That insight became a marketing campaign: "Take your favourite coffee with you, even when you travel."
You cannot get these insights from analytics. You have to ask.