To pick nits, I think the defining characteristic of a job is that one earns money for one’s time and effort. Otherwise, it’s volunteering or a hobby — both of which are fine activities in which I’ve participated over the years — but they’re not “jobs.” In the case of a hobby, one should do it because one loves it and / or gains from it. In the case of volunteering, if you’re doing the work only because you love the activity, you’ve probably missed the point of the undertaking.
