So basically, the person at the top of the scoreboard is the person who’s played their class the most effectively. They’re the guys who healed the most teammates, or blew up the most enemy tanks, or kept the front line supplied with ammo. Basically, they’re not the people who are best with their guns, but the people best at helping their friends. And that’s an important dynamic.
From the Rock Paper Shotgun review of Battlefield Bad Company 2.