While everyone's pitching their helpful ideas, I guess I'll give my 2 cents as well.

A lot of RPs that I start end up coming to completion. Part of it is because I've been [s]failing[/s] doing this for a long time, another part is because I have a lot of [s]autism[/s] determination, and I'm not one to give up on an RP just because a few people leave, or if even my favorite people leave. My Danganronpa RP is the first RP I started on this forum about three months into my membership, and it's going to have a satisfying ending right at the 4 year mark. That's going to happen because I decided to keep running the RP when most of the players left, and was willing to wait out some long hiatuses to make things work. And of course because I have players that I am willing to put that kind of effort in for. They have been just as patient and tolerant as I have, and are a large part of why I'm willing to hold out for them. Hell, they had to kick my ass into gear a few times and they probably didn't even know it. But it [b]does[/b] take effort.

But that's sort of the exception. Usually I run an RP for a year or two with an end in mind. And hey, sometimes even those fail. Doesn't matter too much to me though. I've got great memories of RPs that didn't finish, and friends I made along the way. Yea, completing an RP does give you that rush of accomplishment. Like hiking up a tall mountain and conquering it. But even if you don't conquer the mountain, the hike can be its own reward.