Once you see that an answer is not serving its question properly anymore, it should be tossed away. It's just their natural life cycle.
They usually kick and scream, raising one hell of a ruckus when we ask them to leave. Especially when they have been with us for a long time.
You see, too many actions have been based on those answers. Too much work and energy invested on them. They feel so important, so full of themselves. They will answer to no one. Not even to their initial question!
The hardest thing about customer interviews is knowing where to dig. An effective interview is more like a friendly interrogation. We don’t want to learn what customers think about the product, or what they like or dislike — we want to know what happened and how they chose... To get those answers we can’t just ask surface questions, we have to keep digging back behind the answers to find out what really happened.
A pattern which prevents us from resolving our conflicting forces leaves us almost perpetually in a state of tension.
For, if we live in a world where work is separated from family life, or where courtyards turn us away, or where windows are merely holes in the wall, we experience the stress of these inner and conflicting forces constantly. We can never come to rest. We are living then, in a world so made, so patterned, that we cannot, by any stratagem, defeat the tension, solve the problem, or resolve the conflict. In this kind of world the conflicts do not go away. They stay within us, nagging, tense…The build-up of stress, however minor, stays within us. We live in a state of heightened alertness, higher stress, more adrenaline, all the time.