There is a classic cartoon about the hilarious results of mis-communication when building custom products for customers.
This in fact happens in the Real World. Not only in software, but with physical products as well. For your consideration: here is what happens when you build infrastructure without any User Experience Testing. Doing user testing comes a little later in the process, but is still a critical component of the conversations you need to have when Building The Right Thing.
Building the wrong software product is expensive. People are expensive, time is expensive, and some mistakes (lost time, lost money, broken relationships) can’t be undone. We can avoid these problems with careful conversations at the beginning. We need to identify needs, ask the right questions at the right times, and direct the conversation as needed. When done correctly, actually understanding the problems we’re trying to solve before trying to solve them results in massive savings for everyone.