Even more disconcerting, it can sometimes be very hard to tell the competent from the incompetent until you have them in the door working for you.<p>I once worked with a guy (not in an engineering discipline) who could talk circles around much more competent people. He knew all the buzz words, and even knew most of the topics about one level deep. When he spoke, he spoke with an absolute air of authority on whatever subject he was talking about. He managed to convince division manager after division manager (he jumped around a lot and it was a very large company) that past failures were just because of circumstances out of his control.<p>However, he didn't actually know <i>anything</i> and every project he was put in charge of either failed disastrously, or was caught from the brink at the last minute by colleagues who worked double shifts to do the project (which of course allowed him to point to those same colleagues as incompetents that he had to deal with on his project and hence the reason for failure).<p>The really sad thing is, I could never figure out if he knew he was grossly incompetent and just spinning things to keep a job far above the level he should have had, or actually believed the yarns he wove about what he knew.