I've been looking over the whole collection of images posted on the site and one thought keeps coming to mind. Too many of these look precisely as though someone had done an experiment or exercise with their favorite software program, added a title to make it sound like a finished work of art and posted it (these titles are, to me at least, patently after-the-fact). The worst of these seem to be missing the hand of the artist entirely---that is, they look as though someone took whatever their computer generated and posted it cold...thinking, I suppose, that whatever their computer generates must be both finished and good.
A number of years ago I was one of the judges for a national digital art competition. When I got the CD containing the entries, I was able to immediately throw out more than a third of them. These were works where it was obvious the artist had put nothing into the artwork other than the parameters demanded by their software. I didn't see any in which it looked as though the artist sat back and asked themselves, "Is this any good? Does everything look right?"
A related mistake is the digital artist who assumes that digital art by its very nature must be good. As a result they don't put their artwork through the same gauntlet that any traditionally created work would have to pass. They don't (apparently) even think of asking the same questions of it or holding it up to the same standards. Unfortunately, their work is not exempt from these criteria.