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.
Where long the shadows of the wind had rolled,
Green wheat was yielding to the change assigned;
And as by some vast magic undivined
The world was turning slowly into gold.
Like nothing that was ever bought or sold
It waited there, the body and the mind;
And with a mighty meaning of a kind
That tells the more the more it is not told.
So in a land where all days are not fair,
Fair days went on till on another day
A thousand golden sheaves were lying there,
Shining and still, but not for long to stay—
As if a thousand girls with golden hair
Might rise from where they slept and go away.