Reason #83 why Tony Hawk is the only pro skateboarder I know by name.
I should start out with the best part of this game- the trick system. X jumps, Square does a flip trick, Triangle grinds, and O does a grab trick. There are a HUGE number of tricks to do, and when you add this to the huge environments you skate in, it creates a ton of fun. Comboing tricks together by doing a manual/nose manual(You'll learn the skateboarding lingo pretty soon) for tons of points makes it challenging to master, and There's no one path for a good combo. Grinding is probably the best maneuver, It's a great combo chainer and lets you pick up speed fast.
You have specific objectives for each stage, in the main mode, classic, you have two minutes to accomplish at least one of these per try. Once you have completed an objective you won't have to do it again and sometimes new ones open up. They range from getting a certain number of trick points, grinding a specific rail to trigger an event, performing a certain trick, or finding a secret tape in the level.
So why an 8? On the bad side, a few of the levels are sort of boring and uninspired. The fun ones have a lot of different objects to grind on besides just ramps or rails and are large to encourage exploring. They have a level creator, which is awesome, but I never preferred it over the regular levels. It's not really a game you're just constantly playing, because after you've done certain tricks hundreds of times they do get boring. It's more of a pick up and play game that is just plain fun.
The graphics are pretty good, especially for one of the PS2's first games. The sound, well, I guess isn't bad, I'm just not a fan of the kind of music in here. I suppose it does fit the skateboarding theme, though.
Everyone needs to play a Tony Hawk game once in their life, This game is just as good as even the newer ones.