Interesting.

Question:

What causes the cupping? Is it alignment or is it the tire? I had the car aligned at the first annual maintenance time. What is curious is that the two tires on the driver's side are cupped, but the passenger side is not (yet?). Someone told me it was because the tires were not rotated. However, the manual says that BMW does not recommend rotating tires. Any ideas? If I spring for the Michelin's will they cup in 15k?