At first this was something I never quite understood involving design. When I watched the Eames documentary the architect and the painter I was exposed to it. Because sitting in class in art school you feel as if learning comes from a teacher and not the process.
This is also in relation to learning how to play sports. Not saying that you cannot learn from books but the real learning comes from doing. Nowadays there is unbelievable amounts of free information on whatever subject you want to learn. Because if you want to learn something you have to be willing to go through the process of failing until you become good at it.
In the process of designing you start sketching and then after your done sketching you move to the computer. While working on the computer you see what is working and what is not working. Those moments are where the real learning is taking place in being a designer.