Writing about scientific research:
“A common mistake of beginners is the desire to understand everything completely right away. In real life understanding comes gradually, as one becomes accustomed to the new ideas. One of the difficulties of scientific research is that it is impossible to make progress without clear understanding, yet this understanding can come only from the work itself; every completed piece of research represents a victory over this contradiction.” – A B Migdal (Russian physicist, contemporary of Lev Landau)
I think this applies to other areas as well.