[Rokrin]

Because I don't like Halo period.

Actually, I should rephrase that. I don't like the direction Halo has taken.
The first one was genre defining and epic, I still play it on a daily basis.
Halo 2 was...meh. It introduced some wonderful concepts and basically set the standard for Xbox Live, but aside from that it wasn't that much better than the first.
3...3 broke me. Some of the stuff they did in it was just bad, and the majority of people who play it are so young that they think throwing sexual slang over the microphone every 1/2 a word makes them cool. And yes, I realize that that's a complaint more about the community, but they rehashed so much over the course of those 3 games that I actually predicted the Halo 3 course of events and was right (including Master Chief's "death", but I couldn't predict exactly how he was going to be kept around because there was no indication save the face that Dr. Halsey, Kurt, Kelly and ilk are all still on the Forerunner Shield World.)

I'm not saying the game is the epitome of all evil, but it could have been a lot better. And I really don't want to see the same thing again.

Now, that being said, if they made a game about the Spartan-III's, THEN I would buy it. Because damn they're cooler than the II's. XD