Usually not popular right away, but eventually. Contemporary reviews of Thelonious Monk said his music was crap. Now you get it in the elevator. And "art," the real thing, often changes the way beauty and composition are understood.
Yes, yes! Recordings of Monk reveal a beauty that develops during the course of his often-not-so-beautiful moments. May take a couple of revisits, much like appreciation for actually artistic photographs.
I note that PB refers to Smith's pictures of the soldier and the baby as "beautiful;" certainly not clouds, blurred water sunsets and young girls. I did not mean "pretty."