[woofie11]

It's one of those things, if you've ever managed a larger team, that's incredibly, incredibly obvious.

A single bad hire can suck up the vast majority of your management time, drain team morale, drain it further when you inevitably fire them, open you up to liability, and generally make your life miserable.

Bad hires do slip in, and each time they do, BOY does it suck.

You need a study for this just about as much as you need a study for "Don't touch the kitchen burner."