Magnet

That's the only thing I can come up with. Some joker at a Subaru plant thought it would be funny to embed a high-powered magnet in the rear driver's side wheel of my car. How else to possibly explain the fact that I've had three punctures, leading to three completely destroyed tires, in a little over a year? And every single one of them was the rear driver's side tire. I just don't get it!