Well, let's see. Our theater has a surfeit of wonderful actors, designers, and directors. It must be a lack of playwrights that can people the stage with characters acting on each other, by which I mean, characters trying to change or influence or thwart or love (or whatever active verb you choose) someone else that becomes a complete plot.
So underemployed actors find themselves with time on their hands and write monologues-cum-standup routines for themselves to appear in. The one handers aren't bad but they're not a full experience of theater.