The point of most things is to enjoy them. Friendships, family, hobbies, projects, marriage, and so on. That's even a pretty decent take on the meaning of life. I'll admit that sounds a little hedonistic and selfish on first pass, but hear me out.
- My best friends are the ones who really enjoy my friendship.
- If you love what you're doing, you're generally a more interesting, positive, fulfilling person to be around.
- I don't want to trade places with anyone who disagrees with me.
In other words, by being selfish in a healthy kind of way, you become happier and you make those around you happier. In fact, I'll go so far as to say that in order to be ethical, you must strive to enjoy yourself because your happiness directly affects the happiness of those who love you.
Now you can make a convincing case that enjoyment is not the point of your job. You need to make money and it's amazing if you can not want to kill yourself doing it, but frankly who really wants to work.