Don Norman quote from The Invisible Computer:
"Don’t ask people what they want. Watch them and figure out their needs. If you ask, people usually focus on what they have and ask for it to be better: cheaper, faster, smaller. A good observer might discover that the task is unnecessary, that it is possible to restructure things or provide a new technology that eliminates the painstaking parts of their procedures. If you just follow what people ask for, you could end up making their lives even more complicated."