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.
The horizontal axis represents the investment the organization makes. As investment increases, the organization spends more resources on improving the quality (remember, Noriaka was a quality guy at heart) or adding new capabilities.
The vertical dimension represents the satisfaction of the user, moving from an extreme negative of frustration to an extreme positive of delight. (Neutral satisfaction being neither frustrated nor delighted is in the middle of the axis.)
It’s against the backdrop of these two axes that we see how the Kano Model works. It shows us there are three forces at work, which we can use to predict our users’ satisfaction with the investment we make.