“In some of [your music] you seem to me too easily satisfied. One ought never to forget that by perfecting one piece more is gained and learned than by beginning or half-finishing a dozen. Let it rest, and keep going back to it and working at it, over and over again, until it is a complete finished work of art, until there is not a note too much or too little, not a bar you could improve on. Whether it is beautiful also, is an entirely different matter, but perfect it must be. You see, I am rather lazy, but once begun I never cool down over a work until it is perfected, unassailable.”
— Johannes Brahms, 1876, from a letter to Georg Henschel.