That's now. Look back to their FailWhale period. They certainly didn't have "best of the best", yet they did succeed. Though I guess you can count Arrington's constant cheer-leading as the best of marketing... but it'd still be a stretch.
> Why do you think Spolsky started his career there right out of college?
Because of their stock option program, why else. But that's irrelevant.
Microsoft did not succeed because they had "best of the best", but because of their underhanded sales and customer entrapment tactics.
Point being the company don't need "best of the best" to succeed. It's often sufficient, but it's certainly not necessary.
Solid teams and people get to be named solid only after they perform.
You are looking at those companies after they won, but when they started and with no proven credentials against them I doubt you would have the same view about them then.
Microsoft the hot late 80s/90s company was where the best of the best went. Why do you think Spolsky started his career there right out of college?