Everybody has their reasons.
An artist must eat sparingly and give up a normal way of life.
I've never let one day go by without painting, or at least without drawing.
One must from time to time attempt things that are beyond one's capacity.
There are two indices of genuine art: it is inimitable and it is ineffable.
In painting, as in the other arts, there's not a single process, no matter how insignificant, which can be reasonably made into a formula. You come to nature with your theories, and she knocks them all flat.