doubleKO said:

Nailed it! 1983 Jabba looks better than anything ever made on a computer. I totally agree that something can look crappy but knowing that it is really there makes it more immersive. Lucas has had two shots at CGI Jabba now and neither of them begin to approach the illusion of a living creature the way the puppet does.

I suspect this has something to do with the puppet never crawling around. I don't think it's the only issue, as the Jabba puppet really is pretty amazing, but I think it's part of the problem.