Kevin Clark of the Wall Street Journal has a fantastic look at Bill Belichick's coaching style at the Patriots facility. The Patriots head coach wants his team to be the most prepared unit on the field, so they can react without having to digest what is unfolding on the field. He does it by questioning everyone.
The questions can be things that are noticed on film—like a subtle trait of an opponent—or they can be biographical, like when an opposing player joined the team or what his background is.
The variety and seemingly random nature of the questions can cause a degree of panic in the locker room. You will find Patriots hunched over internet browsers, scouring for information on anything and everything. "You just have to Wikipedia, Google, SportsCenter, use your ESPN app, something. You do what you’ve got to do," said cornerback Kyle Arrington.
It's easy to see why some players can't make it in the Patriots system; and it's also clear to see why Belichick dips in the same college well for his prospects (like Florida or Rutgers), because he has their college coaches vouching for the prospect's cognitive ability.
Go read the article. It's a fun one.