Artist David Salle once overheard Jasper Johns saying, “the first obligation of a painting is to make the wall look better that it’s hanging on.”
There’s certainly that, says Salle, as well as a dozen more jobs that a painting can do, including saying something about its author, its owner, and the time in which it was made, for example. A good painting checks most or all of the boxes.
I’m not a painter, but if I was one, I’d want to know what a painting is for, as it tells me which boxes I should check. I’d also want to know what’s a painting’s first obligation. I may disagree with Johns about what it is, but I’d decide what it is for me up front, so that if a box has to remain unchecked for any reason, I won’t let it be just that.