[XT6Wagon]

OEM tires are often molded shallower and with cheaper rubber compounds than the retail tires. This is so the Car maker can put a set of "$1000" tires on thier cars for as little money as possible. I've read that these OEM sales are often at a loss for the tire maker, but they do this so that Bob when his factory tires wear out goes back and buys the same brand/size thinking thats what he has to do.

We also are getting much better tire compounds. This means they can run a softer compound without highspeed/high heat safety issues. Softer means better traction in snow, wet, and dry. Yet more wear.

Last it seems that people are poor at choosing a proper tire design and compound for thier car. Including OEMS. The RE070's on the STi wear like iron if you drive normal and even hooning it are fairly long lasting. They trade noise and subfreezing performance for it. Highpowered cars will all do much better with "summer" tires as these resist wheel slip and wear less. The more sipes in the tread the more wear from burning out or skidding. So a 800 treadwear tire on say... A viper would last a fraction of the time of a proper 200 treadwear summer tire. The reverse can be true also. Driving a normal family car with ultra conservative alignment the ultra deep tread of the 800 rated tire will last longer than the 200 since the minimal wear per mile will be equal, yet the one tire will have 2 or even 3 times as much depth before being illegal to run.