Picasso left art school at the age of fifteen, on the grounds there was nothing more they could teach him. This is extolled in biographies of Picasso. Unfortunately, he never learned perspective. In his realistic period, early in his life, there's never a room with perspective. He puts a figure or two and a stick of furniture in the foreground, and everything beyond them is fog. He never really learned anatomy. In many of his realistic pictures, fingers and thumbs are like a bunch of asparagus that you buy in the grocery store. He was never very good on things like foreshortening. If I were as ill-prepared as Picasso or Braque I would have thought up a name like Cubism, too, as a way of legitimizing one's lack of skill.