I read a book that could literally be summed up in a sentence (it was called "the asshole rule" or something similar, and the gist was "don't hire assholes"). There was nothing at all in addition to that, except for a bunch of feel-good anecdotes and specious data that misrepresented correlation for causation.

I hated it so much that I made a (now defunct) website where I would post summaries of these books so people wouldn't have to be subjected to all the filler.