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.
As George Lakoff and Mark Johnson made clear in their touchstone book Metaphors We Live By, metaphors are the basis of all human thought and reasoning. The metaphors we use to speak about the web are not simply linguistic trivia – they determine how we understand it on a fundamental level. It determines what we think the web is capable of, what risks, opportunities, and challenges it poses. Which means the metaphors we use to think about the web profoundly influence what we think the web is, what we think we can do with it, and how we might change or evolve it.
…Out of all of these metaphors [for the web], the two most enduring are paper and physical space.