I like the insight: Companies keep the good ones (presumably) and the only people available for hire are the unwanted. (I'm not being snarky, but look what happened when Ford fired Lee Iacocca.)
Too many people are not being fast-tracked or, if you prefer, mentored. Think back to your school days. Didn't everyone know who the bright kids were? At recess, didn't everyone know who were the "captains" for soft-ball, kick-ball, etc?
"When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." -- Jonathan Swift