Just to offer a differing POV...
My first long fic was written on the installment plan. Those were in the days before I started using a beta, and I was more or less using the message boards readers for that purpose. It worked out beautifully for me, because I was such a tentative newbie at the time that I *needed* the feedback and encouragement. And the details. I hadn't yet seen the ep I was rewriting, which made things a little complicated.
The positive responses spurred me on and gave me impetus to continue. Honest feedback *did* cause me to change a few small points in two scenes, but I always had my final destination in mind and wasn't too distracted.
My second long fic, OTOH, took... oh, about nine months or so to complete. :rolleyes: So I do agree that posting-as-you-write doesn't always work. It sure didn't work for poor Lara and Jor, whose Last Adventure of Krypton are still stalled (one day... one day...). But I did want to point out that while many people prefer to have their story complete before posting, you don't need to hesitate if you want to try it the other way. We'll take fic any way we can get it!
Hazel