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.
Markkula wrote his principles in a one-page paper titled "The Apple Marketing Philosophy" that stressed three points.
The first was empathy, an intimate connection with the feelings of the customer: "We will truly understand their needs better than any other company."
The second was focus: "In order to do a good job of those things that we decide to do, we must eliminate all of the unimportant opportunities."
The third and equally important principle, awkwardly named, was impute. It emphasized that people form an opinion about a company or product based on the signals that it conveys. "People DO just a book by its cover," he wrote. "We may have the best product, the highest quality, the most useful software etc.; if we present them in a slipshod manner, they will be perceived as slipshod; if we present them in a creative, professional manner, we will impute the desired qualities."