Uneven wear can also be the result of a mechanical problem with the car.
If the tires aren't aligned properly, some of the tires will tend to
"drag" and wear poorly. Worn-out suspension components can alter the
weight distribution, particularly when cornering, adding to tire wear.
Tires that are improperly inflated will also wear unevenly. If you want
to see what uneven wear looks like, check out the tires the next time
you rent a car. Car rental companies are notorious for not rotating the
tires on their cars regularly -- combined with the heavy use they
experience, rental cars often show very uneven wear.
