Story involvement, says Soesbee, begins with players' avatars as early as character creation. Grubb talks about the balance between creating characters with depth and characters with enough loose ends for an unexpected story to emerge, which is a fine line to walk. The game is built around the assumption that players are heroic in nature and essentially good. Like in the original Guild Wars, players don't really have the option to be villains or anti-heroes through the storyline. The liveliness of NPCs and the world around characters are also key steps toward drawing players into the game.
I think that's what it all boils down to in the long run-you become emotionally invested with the game because you become interested in both your character and the world. And you can do that by making choices and seeing those choices have an effect-and truly matter-within the world. That is one of our goals when we're telling stories in Guild Wars 2. - Jeff Grub