It really is a weird fairytale, and it always feels to me that it might have originally been several stories that got smushed together.

I still haven't read Divergent, and don't particularly want to, but I can well imagine that the series started out with one strong book, and then got expanded into a poorly thought out trilogy. Certainly with The Chosen Ones there was a good idea, but it was buried beneath a whole lot of rubbish.