I’m going to offer up just a few points built mostly on anecdotal evidence as regards these models.Link (via Wonderland)
First, that Achiever to Killer is a very common path. Once the game’s opponents are no longer interesting, being limited by crude AI, actual other players offer a better challenge. A lot of people never want to take this step, and it’s arguable that they are driven not only by the fact that they dislike PvP, but also by the fact that they are statistically certain to lose most of the time.
Second, that in many ways, we are all heading for a Socialization Destination. Everyone gets bored of a given virtual world (again, cf. Theory of Fun). They then hang out there only because it’s where their friends are. The games in these worlds are like the beer at a bar, the rides at a carnival. They are diversions, and the point for most ends up being the other people.
Third, that age, gender, and behavior are intimately related. Aggression is tightly linked with certain playstyles, including achievement. Anecdotally, many of the most aggressive players I have dealt with have been people in aggressive, confrontational, or dominant roles in real life, such as cops, lawyers, and the like. And of course, teenage males charged up on testosterone tend to drift to the aggressive roles as well. But as they age, older males tend to act more like female players do all along, losing interest in the overtly aggressive play.
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.