An interesting discussion is going on over at Novelr about what are good novelogs: The forms they can take and interestingly, how they are written. Several people have said they are writing their novelogs as they go. They don't overly plan; they just write.
I'm not one of them. Scary Mary and Unicorn Bait are both fully written. The reason I serialized was to force myself to edit them and then to be done with them. I find that if I don't set deadlines for myself, I will endlessly tinker with something. Conversely, it helps to have myself on a schedule. I'm forcing myself to steadily edit my work. I'm not letting myself slack. Too often with writers and artists, we go through manic creative spats and then doldrums. It's not healthy and doesn't make our work better. A lot of writing books (like Bird by Bird) recommend writing every day, especially the days you don't want to, to make you a better writer. It's the same with editing. Edit steadily, and the editing gets done. It's as simple as that, but sometimes the simplest edicts are the toughest to follow. That's why I'm posting the stories in a blog.
That doesn't mean I had all this stuff planned out when it WAS written. Unicorn Bait was written mainly during Nanowrimo a few years back. I'm doing some serious overhauling of the plot now, and the reason I'm having to do this overhauling is because how the story began is not how it ended. Plot twists that cropped up at the end have to be hinted at or at least made believable. I couldn't do that if I were posting all of this as it were written. And I think the story would be less if I were posting it as it were written.
I'm not sure if I could write something by the seat of my pants, as wincing.at.light describes his process. My first drafts are just too mangled.