The theoretical reason is to do with immersion. MMOs are virtual worlds: people play them to get away from Reality. In an MMO, you can be someone else; by being someone else, you can become a better you. Why do people play the same game for hour after hour, night after night, week after week, month after month? It’s not because they like the game; it’s because they like being who they are.
When players play characters different to themselves, this can influence both their real self and their character. Much of playing an MMO involves making tiny adjustments to your perception of yourself and to your perception of your character until eventually the two align. It’s as if there’s a dialogue between them, the resolving of which affirms (or reaffirms) the player’s sense of identity.
It’s a quest for identity.
By being someone virtual, people find out who they are for real.
It’s an identity thing. The more you feel that your character is you, the more immersed you are. When the two finally become one, the result is a persona—you, in the MMO.
That’s immersion.
Imagine a line showing a spectrum of identity. Yes, I realize this is a tall order, but bear with me. Put a box on the left of this marked P, which shows the player’s sense of self when they start. Put another box on the right marked C, which shows the character the player has created. A third box in between, marked H, indicates the hero—the renewed sense of self the player gets from having played the MMO and completed their hero’s journey.
Playing an MMO—or a virtual world in general—is a hill-climbing exercise through identity space. The hero’s journey is a good algorithm for finding a local maximum. Through playing, you get to affirm who you are.
Or, put another way, you are a multi-faceted diamond. Playing an MMO means you get to see more facets of yourself than you would in ordinary life.
Richard Bartle, MMOs From The Inside Out