I found this article that might explain the reason...
"Why does it seem like guys like video games more than women? I'm sure there are plenty of women who like to blow stuff up and battle monsters. But, it's mainly a guy thing. So why is that?
That's what Fumiko Hoeft wanted to figure out. She's a researcher with the Stanford School of Medicine. She arranged a pretty cool experiment. She got 22 Stanford undergrads -- 11 men and 11 women -- to play a video game inside an MRI scanner, a machine that allows scientists to see what's happening inside the body.
As the young gamers were in the MRI machine happily playing away, Fumiko took a look at what was happening inside their brains.
"What happened was that both men and women showed activation in regions that are related to the reward and addiction circuitry, but what was interesting was that there was significant difference in the amount of activation and Specifically, the men's brains were much more active than womens. "
But the object of the game was telling. By clicking the balls in a certain way, the players could gain or lose territory. And men were significantly more hyped up by this challenge.
So in the end, Fumiko's point isn't that - men like video games more than women. That probably depends on the game.
It's about how males seem to be more hard-wired than women are to get excited about claiming and conquering territory. Maybe that's why so many video games are about war and mowing down wave after wave of enemies & conquering territory. They're designed to appeal to the latent conqueror in men.
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Also I think guys want to finish what we started. .Thats why finishing a mission in a game sometimes becomes an obsession with us... Dont think women gets exited about this as we do..