Most first-novels are therapeutic for the novelist, who manages to get a whole lot of stuff off his chest and out of the depths of his subconscious and frees himself to WRITE. Unfortunately, this also means that most first novels are unsalable, but the writing can have major benefits for the writer in personal development.
Since I've found writing very therapeutic, and believe that when you consciously use writing as a personal development process it improves your writing skills, I'm starting a new "writing as personal development" category.
Are you using writing as a personal development tool? How? Please leave a comment.