My method for determining great art is very simple. I stand in front of the painting. I look at it. And I feel.
To me that's the bottom line. I don't care how a painting was made. I don't care about "process" or technique. I don't care if the artist has "brought something to the table no one's ever seen." I don't care about theory of any kind. I don't want an explanation and it doesn't matter to me how many "art minds" have given their imprimatur or how many rich idiots have bought it. Bottom line: How does it make me feel?