To be fair, I've gotten plenty of deer in headlights style blank looks from "geniuses" at Apple stores.
Apple hires people more on personality than any kind of technical skill. While it does happen, the intersection of the two is very rare. Apple goes for the very pleasant, but technically dubious sort, while most other places go for the more skilled by maybe a bit socially inept. But of course it's retail, so usually they get paid crap and the people who have any real skill find a better job somewhere else before long. Then you're left with the people who either have a lack of skill, or some other severe flaw that keeps them from going somewhere else.
I've gotten units in to me that were diagnosed first at Best Buy and they claim it's a logic board when it's just a bad HDD. I've gotten units in that were diagnosed by someone at an Apple store where it's pretty much the same deal. They claim it's the logic board, and the actual problem is the HDD. You get morons working for Apple same as Best Buy, Fry's, and probably any other outfit you want to name. You'd hope the bad ones would be fired, but usually it's the opposite because of what I said above. The good ones find other jobs, so the bad ones keep their jobs so the store has bodies to man that particular part of the store. You just have to hope that you luck into one of the good ones before they go elsewhere.