Rampant Games - Encounters as Boundaries
A short piece from Tales of the Rampant Coyote on encounters as "soft boundaries":
His philosophy - which I adhere to - is that it is far better for the players to choose to follow the prepared course of the game than to be forced to do so.
More powerful enemies in CRPGs are one example of a (sometimes frustrating) "soft boundary." The player isn't prevented from making a run into the deep end of the pool while still in the early stages of the game, but the difficulty of the encounters may convince her that it's more profitable to go back to an earlier area to pick up some quest threads. But the possibility of heading into more dangerous territory remains open ... maybe to make a mad dash to another town that sells more powerful equipment. Why not? In the past, these kinds of self-initiated quests have proven to be among the highlights of several games I've played.
An essential part of a great RPG, for me.