I would say you're either very hard on the brakes - not uncommon when someone drives a car with good brakes - they aren't releasing as Jim says, or there's something wrong with your rotors that are chewing up the pads. I have 24k miles, including 5 track days in the advanced or instructors' group, and probably 15 autocrosses - hard to keep track - and still have plenty of brakes still on the stock pads that came on the car...

brad

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21-year PCA Member
PCA DE Instructor