The old days’ pictures went forward toward completion by stages. Every day brought something new. A picture used to be a sum of additions. In my case a picture is a sum of destructions. I do a picture – then I destroy it. In the end, though, nothing is lost: the red I took away from one place turns up somewhere else.
Statement by Pablo Picasso, 1935
I can hardly understand the importance given to the word research in connection with modern painting. In my opinion to search means nothing in painting. To find is the thing. Nobody is interested in following a man who, with his eyes fixed on the ground, spends his life looking for the pocketbook that fortune should put in his path. The one who finds something no matter what it might be even if his intention were not to search for it, at least arouses our curiosity, if not our admiration.
Statement by Pablo Picasso, 1923
read the whole text here