It is due to the rotor and pad composition. If you have ever driven a Mercedes or Porsche they stop amazingly well, they also go through rotors very fast as the metal is softer than most other makes. We have a lot of local customers that have wanted to upgrade there brakes, but insist on keeping the stock wheels. For those folks and the budget minded, this kit is awesome. All of the kits I have seen have not offered a curved vane rotor to keep from fading the brakes and still retain the stock wheels. We have a customer (Jason) that tried a few different ways and always warped the rotors very fast. Jason pushed us to bring this kit to the market and he was our first test car. I went for a canyon drive with Jason after he had tested the kit for a few weeks. THIS GUY PUSHES THE BRAKES WAY beyond what I would consider normal and I was amazed that the brakes were not fading. This guy is an animal. (Anyone that personally knows me realizes when I say that that something must be up ;-) ) After pushing the car beyond reason for 30 minutes in the canyon, I asked Jason to make a few 100 to zero stops and to my amazement the car came to a extremely fast stop to where I must have had marks across my chest from the seat belts. After all this I took over the wheel for the canyon drive home. The brakes stopped the car as well as my full big brake kit, but did require more pedal effort due to the smaller rotors having less leverage. For a kit in this price range and especially for those wanting to keep the stock wheels, this kit is all of that and a bag of chips! Enjoy!!