It depends on your view point. A lot of art is critized for the artist's abilities and techniques to create the art and much less for the subject matter. The David could have been any random dude, but it is the ability of accurately recreating that randome dude in stone that makes it impressive. Some of the painted pieces that are extremely large and take up an entire museum wall are impressive just for the shear accomplisment. Yes, it helps that it looks so real as well.

>See also: displaying unfinished sketches. Nice for a collector but let's not pretend there's any artistic value in it.

If you imagine those sketches being underneath the painting and realizing that those sketches were how the artist worked on creating the actual piece is interesting in the same way watching behind-the-scenes videos on how a movie was made are interesting--to those that are interested in the first place. Similar to Show HN articles on some use of fad language to redo something else already in existence. If you have no interest in that language or the thing being made, they aren't interesting.

> See also: displaying unfinished sketches.

Depending on the artist and the sketch, I'm quite happy to see it also. Sketches can provide a lot of super interesting context about other works. And sometimes they're quite good by themselves.

There's also no "value" in watching, say, Novak Djokovic practice his serves. Unless you care about tennis, in which case you'd probably watch with rapt attention.

Same thing, basically, for sketches by good and/or important artists.

IMHO unfinished sketches by great artists can be amazing little stories unto themselves. They can give you insight into the creation process of the artist, which fascinates me. And sometimes they are even more fresh and dynamic than the finished work.

I once rode in an original Model T. Ride was horrible: super slow, very uncomfortable, and the handling was ghastly. But clearly we don't judge "ancient" developments exclusively by modern standards...

Artwork of old was commissioned and preserved by the wealthy. All of the old works are rare (relatively), fairly impressive for the time, and some are true masterpieces.