Profit, I guess. The market for visual novels (outside of urban Japanese society anway) is, as we all know, rather small. The author knows what they do best, which is to put words together in the hope that it will attract a readership. An author simply wants to write because they enjoy the medium with its rich history and enormous potential. Why should they go to the extra trouble to hire a director, a programmer, and an artist to sell their story? (in general authors aren't rich to begin with!) Visual novels are a hobby enjoyed by a specific demographic with access to that technology. You may find a novel in developing countries, but I doubt the majority are even aware that visual novels exist. (Choose Your Own Adventure Books, maybe) As a hobby, its biggest pool of creative talent inevitably comes from the hobbyists themselves - who have the time and interest to contribute to and expand the visual novel community.Instead of asking why visual novel writers aren't tackling other subjects, ask why authors in general aren't tackling visual novels.
In a way, I guess the visual novel community in its current state is a sub-culture of a sub-culture? I think someone brought that up before. It could be...counterculture? :| We're rebels, all of us. :P


