They're easy to spot.
They need a few minutes of quiet after getting in to work. They might love teaching, but after a 60 minute lecture or two, they are drained--mentally and physically. They might prefer to eat lunch alone to get some more energy before the next lecture or meeting. They need time at home to recharge for the next day.
It's the introverted professors!!
(Raise your hand if you are utterly drained from your first day of classes....and not just because of your workload.)
