Sometimes you're not even sure which of your stories were failures. There are things I've written that I thought were complete catastrophes when I finished with them that have gone on to generate some...
People who were more concerned with themselves and looking good to their readers then they were with the characters sacrificed a series for the sake of a story.
I've always thought of myself as an organic writer, rather than a cerebral one. I feel my way along as I go, hoping I'll get to the place I intend to reach.