The biting off more than you can chew issue is particularly common in the larger, well-established universes.

One prime example of this is the [i]World of Darkness[/i] setting. We've yet to see a single RP there last more than a few weeks or so. The vast majority we've seen there, permitted characters from all the core settings (vampires, werewolves, changelings, mages, etc...) which in the end meant that few if any characters had much of any reason to interact. Even when it is limited to just one of the core settings, like [i]Vampire: the Masquerade[/i], there's quite a few clans to choose from, which can lead to the same lack of interaction options.

Its all well and nice with a vast setting, but sometimes, smaller ones with clearly defined limits are easier to set up. We ourselves are approaching launch of a massive Star Wars RP, within which we hold rather strict limits on the types of character allowed, simply to make sure that people will interact. In a galaxy as vast as that one, the players will be forced to be primarily upon one or two worlds, despite there being all sorts of other worlds out there too. This again, is to keep them together, where they'll interact.

It has not got a clearly defined end, but that is quite simply because we don't yet know where the characters will take it. We've got several options noted down, but who knows if any of them will be applicable. We've made plenty of mistakes in its execution in the past, as this will be the third time that RP is launched, each time redesigned to take care of the major issues that popped up.

The players, spread out across 3-4 factions, will drive the plot themselves, and however they end up doing stuff, that's where the story will go.