I find it implausible that the threat of being fired is the only good way to motivate workers. It definitely seems like some companies are much better run than others, doesn't it? How do you think the best-run ones are well run? Probably by hiring the best people and having a great corporate culture. Here's a good Aaron Swartz piece on this.

Is that a special case of a more general belief that if there are lots of top-selling books about how to do X, it follows that people can do X in an intentional/systematic way?

To a degree I'd expect that to be true, especially if the books are written by smart, credible people, which is how I tend to perceive the authors of the best business books. Certainly much more credible than the folks who write books on how to win the lottery scientifically.