I write my Hubs as a form of self-expression, I guess. Much like some people keep a personal journal, I put my thoughts 'out there.' Well, much of the time. At others I endeavour to teach people. I'm vain enough to think I know something about certain subjects which might be helful to others e.g. Storytelling, or Creative Writing. Also, some views on Self-knowledge and self-understanding.
Or I might simply put up a poem or short story or something I've had an interest in at some time. But writing for money on Hubpages has hardly crossed my mind, if only because from the chatter on 'Answers' it is almost impossible to make anything other than a pittance anyway.
No, I do it for the fun.