In the long run, No one does anything for anyone except for themselves. You don't get out of bed at 4am to train clients just to change lives.
You don't go to course after course because someone told you to.
You don't miss birthdays and events just because you don't want to let someone down.
You do it because in some way, shape or form, it will benefit you.
It's nice to be nice, but at the end of the day, there is always something in it for you.
It may be money, deeper relationships, career development, more time or just for some good karma.
But don't fall into the illusion that things are any other way.
It's not selfish.
It's called being human.