Uh, no? For the time when I was employed there, they weren't "elsewhere." They were sitting right next to me.

(The presence of incompetent engineers was certainly a factor in why I left that job.)

You should work on your reading comprehension. What you're saying is precisely what the author is talking about: everyone has a story about terrible engineers, but they're almost always "elsewhere". Co-workers tend to become "stupid" and "incompetent" after you leave. And yet they maintain employment.

It's an idea, not an iron-clad rule, that perhaps "incompetence" isn't as rampant as so many people suggest.