Some architects do. There is an old BBC (I think) broadcast showing Christopher Alexander building a house. He goes to the site with the people who will live in the house, asks them what they have in mind. He has a scaffolding built, then asks the people to sit on the scaffolding in different places and talk about how it feels. Based on that, the rooms are decided, and so on. The house is built incrementally using feedback; there is no up-front plan. Admittedly, Alexander is far beyond the pale of mainstream architecture, but this is way cool.