You have to know how to use the accident, how to recognise it, how to control it, and ways to eliminate it so that the whole surface looks felt and born all at once.
Whatever the medium, there is the difficulty, challenge, fascination and often productive clumsiness of learning a new method: the wonderful puzzles and problems of translating with new materials.
We would sift through every inch of what it was that worked, or if it didn't, and wonder what was effective in it, in terms of paint, the subject matter, the size, the drawing.