Warped rotors

To clean the discs up you don't need to remove them to clean them from pad transfer, unless really bad, then just use a grinder with a wire fitment.

To clean the discs I do the following, rarely as once you understand how you get pad transfer you never need to.

Where possible, drive at 70mph and brake as hard as you can dozen to 20mph. Repeat 3 or 4 times, then drive without using the brakes to cool them down. This should clean your discs of the transfer and they should be nice and shiny. Your responsible for your actions so take care.

The main 2 causes unless your pads and discs are not comparable are heavy braking to traffic lights and the just sitting on your brakes. This cooks the pad surface to the disc. Or braking using very light effort to come to a stop regularly. Again pad transfer will happen.

One way to make your brake last longer, take you foot of the gas earlier than you would normally when you know you have to stop. On my last 2 cars I have put on over 40k miles on both and never changed the discs or pads. Observation saves excessive brake wear. Also by braking more heavily for shorter distances helps too.
 
Just an update - 2014 Mazda 6 and with properly torqued wheels and very gentle braking over 40,000 miles I have zero brake problems. The rotors and pads feel like the day I bought the car. I agree there's likely better quality aftermarket stuff out there, but you can drive much more gentle and save yourself a ton of time and money.
 
Heads up, autoanything has 35% off Centric rotors and pads. Centric Premium rotors were $55 each, and Posi Quiet Ceramic pads were $34.

Just under $160 after taxes (delivery included). I ordered the fronts. Rears were cheaper I believe
 
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