Car Guys/Mechanics: what the heck happened?

[kaisersozei]

So here's what the mechanic said: the problem was a slight issue with the cross-steering alignment, the rear of the car was basically drifting to the left. Keeping the car straight caused it to put drag on the right front tire which caused the inside wear. Plus it was under inflated (should have been 40psi but read about 32.) Unfortunately, since I did not have an alignment done in the past year, the tire would not be under warranty.

Got it all fixed with 2 new tires so hopefully I won't be wearing these out as quickly! Thanks for all the tips