Probably proportion. David's right hand holding the stone is massive in comparison to his body. It draws attention to the impending conflict.

Wasn't that done intentionally for perspective's sake, to make him look normally proportioned from certain, expected angles?

Using the grandparent's understanding of "generic", art could be generic, yet still exceptionally good/well executed.

I was reading a comment on a jazz album and it essentially said "expertly done but doesn't move the genre forward so meh."

I think people forget that sometimes you just want a good, standard jazz album.

To do a common thing uncommonly well brings success.

- Henry J. Heinz