. . . The one thing nearly all the partners had in common was they loved their work.That's the kind of job you want to have--one in which you look forward to walking in the door and getting down to business. (By the way, that's the kind of job I have--and have had, ever since I became a law professor.)
This came as a profound revelation. Of course they worked long hours, because it didn’t feel like work to them. They took great satisfaction in the services they rendered their clients.
UPDATE, thanks to a good point by one of my fave buddies: for the first few years of work, you won't know if you love what you do, because you're still learning the ins and outs of your job. Give it time.
FURTHER UPDATE: as to that UPDATE point, see here. My own philosophy, which may have no grounding in reality whatsoever, is that your choices, over time, reflect your psyche's understanding of what it is that you love.