A person should choose a vocation for which he has an inclination.
We find it confirmed in the Gemara that each person is generally satisfied with the way he earns his living. In fact, some people love their vocation. That doesn't mean they are madly in love with it, but they have an affection for that kind of work and they don't want any other kind of work. This is inherent in the way people are created. --Ohr Avigdor Shaar Bitachon