Long ago I coined the phrase "one-hand writing" to describe the habit of some writers of concentrating their prose on what "turns them on." The inference was that, in writing pornography, a person could get into a masturbatory relationship with his characters, leaving only one hand free for the keyboard. Of course it prompted a "who, me?" reaction from outraged writers and editors.
        Well, what about writers who create fantasy instead of porn? Do they also tend to put together stories for themselves rather than the market? Alas, I suspect that practice is not uncommon (although without the sexual stimulus.)  Read a writer's works in the various markets in which he is published and you find they display a common style. That's expected. But there may be another sort of commonality. His stories show that he "likes" certain types of fantastic events, powers and characters. It seems he is constrained by a Dungeons-and-Dragons" type of synthesis in its early stages before the scenarios, characters and powers are developed fully.
        Is this good or bad? Well, it's very good to the reader who "likes that sort of thing." It is, however, very bad to the rest who do not. For instance, some writers are able to handle a child as dominant character. Most do not because they tend to show children "deeper" that they really are. When I see a story with a Pudgy-Patty as the heroine, I page on by. I have that choice. Next time I see an illustration of a kid accompanying a story I pass more quickly. If all writers wrote about little "Patty" I'd stop reading entirely (and possibly miss some good literature).
        One who writes for a long while may become too narrow in his story-culture. He tends to "polish" stories to make them as attractive as possible to himself. Soon he is using "shortcuts," i.e., phrases that make sense only if the reader already "knows" the character. We know how Lucy van Pelt will behave in every situation; that is the shorthand that allows us to enjoy "Peanuts" without having her character developed in every strip. But if she is Peggy in one story and Sissy in another and maybe even

 twins in another, the reader is lost unless she is created anew at the beginning of each story.
       If Lucy is your "stock" heroine, you may be writing for yourself. The only escape is to put her to rest and go on to an entirely different heroine (or hero) for the next story. What do you lose? You lose your huggy-snuggly familiarity with your character. You have to start with tyrannically white paper. You must create a new person, describing her entirely. Your readers need that unless they can get inside your head. No good to say, "She waved her hand in that secret way" if no one knows what "that way" is. There are a few who have managed that - Tolkien comes to mind - but it's risky. He succeeded by using an already-created world - our "memory" of ancient England - and built carefully on it.
        Writers who create serials or stories with sequels are particularly vulnerable. Their "love affair" with their characters blossoms and matures to the point where the nature of the characters starts to dominate the story. When I wrote the (to some, interminable) "Tyne Cross" serial for Vampire's Crypt I knew I had to be consistent since readers of that genre prefer it to be quite stylized and tradition-bound. Margaret Carter, the editrix, helped me by suggesting that I create each chapter as a separate, stand-alone story. When these were finished and polished individually, the tying passages were added.
        What works for me is to write the "pet" things just for myself, never intending to submit them for publication. I can enjoy them privately and polish them endlessly to make them ever more "perfect" for my taste. I can even use them as a workbench to work out plot or character conflicts and weaknesses. No publisher will see them unless my descendants try to pay off my residual debts by peddling my "collected papers."
        The focus of all this is simply stated:
       
         THERE ARE READERS OUT THERE.
         THEY, NOT YOU, ARE THE MARKET.
         YOUR PROSE HAS ONLY ONE PURPOSE
         TO CARRY YOUR IDEAS TO THEM.