Who else thinks the "Mona Lisa" painting is crap? It's always been overrated, and seeing it live did nothing to change my impression. Not to disparage da Vinci's corpus ... but just sayin'.
For reference: https://en.wikipedia.org/wiki/Mona_Lisa#/media/File:Mona_Lis...
It was painted around 1503. Compare to something around the same time -- Lorenzo Di Credi -- http://lj.rossia.org/users/marinni/418072.html
Look at the comparison of detail on the dresses. Look at the hands, and the slightly darker color where the light doesn't reach as strongly on the tips of her right hand. Look at the small details on her face like the lines around her cheek bones -- Leonardo was making striking advancements about how to make portraiture more realistic.
We can copy his techniques fairly easily, but creating the techniques is hard.
On a tangent, this is the soundtrack to the eponymous movie, Pollock by composer Jeff Beal. Give it a listen, while taking a look at some of Pollock's catalog: https://www.youtube.com/watch?v=oD0nFjjUCQo&list=RDoD0nFjjUC...
Like nwatson, I wasn't moved the first time I saw Mona. But understanding her history brought her to life the next time we met.
Throwing paint at the wall like a baby projectile-vomitting rainbow-colored Gerber puree'd carrots?