I don't know much about art - I was never trained in it, nor have I thought too hard about it. I just have some fairly recent observations from a photo exhibit.
The photos were of jazz musicians, mostly playing in clubs, you would have to be over about 50 years of age to be familiar with many. I went with a friend who, aside from his day job, is a weekend club musician and sometimes photographer. We were looking forward to seeing some good photos.
The images seemed pretty grainy, not out of line with ~1960s 35mm available-light work. But they were almost universally blurry. About a half-dozen prints into the exhibit, he turned to me and said, this negative would never have made it into my enlarger. I agreed; these would have been the rejects from my contact sheets. In many, motion blur of the faces made them unrecognizeable, instruments were blurred into shiny streaks.
But on further consideration, we both agreed the images DID have the feel of the dim, smokey clubs. So, although these images would have failed in their day as reportage, they are resurrected 50 years later as art. So I dunno.
I grew up with a photojournalistic outlook, always in a fight against graininess and blur, so I have a hard time appreciating this sort of thing. If I know the photographer was skilled (as in this case), I can accept this as intentional. Otherwise, it seems to be a lack of skill masquerading as art. Just my views as a non-artist.