I have a bad habit of creating not just characters but worlds and entire universes. A classic high fantasy world with more than 5 million years of history, a post-apocalyptic fantasy world, two space opera universes, one with aliens and one without, A contemporary setting with scientific vampires and vampire hunters, A next sunday AD setting with superpowers, Atlantis and immortal aliens. My reimagining of Planet Of The Apes on an alien planet probably comes close to being fan fiction, though the setting and characters are all new. Metternia and my semi-hard sci-fi History of Cybertron fall into the fan fiction categories, but there are few new characters and more reinterpretations of existing ones.
My imagination seems to ill fit pre-established worlds, so I usually run out of inspiration before I finish a fan character to an existing setting. Even my MOTU fan characters exist only as a few incomplete idea sketches and lines of text. Then again, with a mind bent on creating whole universes, I often put thought into specific characters after setting up the environment that bred them.
But in the end, I don't think it even matters. It's all just self-expression and a channel for my creative energies. I'm not doing it for money, or even to please others, I'm doing it because I want to, because I feel the need to. It has therapeutic rather than monetary value. Anything else is a bonus. I consider myself lucky enough to be alive, let alone be able to share my creations with even a handful of people with shared interests. I might feel differently if the last eight years of my life had been different, but right now this is good enough for me.