Question quality is a good proxy for how well you really understand something. This applies for every discipline, but especially for building products.
In early stages, product discovery often starts with questions for your customer about their attitudes about something. In bad research, the questions are too pointed, even though they might not seem to be on the surface. In good research, the questions invite potential customers to tell a story about themselves. These stories often lead to the ground truth around customer attitudes, and ultimately, their behaviour.
This example from Teresa Torres really sums it up:
I recently asked a woman what factors she considered when buying a new pair of jeans. She didn’t hesitate in her answer. She said, “Fit is my number one factor.”
That seems reasonable. It’s hard to find a pair of jeans that fit well.
I then asked her to tell me about the last time she bought a pair of jeans. She said, “I bought them on Amazon.”
I laughed and asked, “How did you know if they fit?”
She said, “I didn’t, but they were a brand I liked and they were on sale.”
There’s a huge difference between what people say and what people do. Good research should always try to get towards the latter.