Basically, the life span of the rear disk brake pads depends on some of the factors listed below :

1. Environment :  This factor is all about  where you are driving your vehicle. If you are driving the car in a city then you are more likely to stop because of traffic and other situation. It more likely to brake while driving a car in a crowded place than on a free country side straight way. One of the culprit is the crowded highways. Going on a hill and taking your car on a steep way makes you brake pads wear a lot faster than normal.
2.  Driving Habits :  Lifespan of the brake pads depends on the habit of driver that how they uses the brake. Some drivers uses the brake abruptly and some of the drivers uses it slowly which increases the lifespan of the brake pads. But brake abruptly when the safety calls for it.
3.  Brake Pad Hardness :  High compound brake pads last longer than low compound brake pads but they need to be warm before their extreme performance. On the other hand, low  compound brake pads are suitable for urban areas.Rear Disk Brake Repair Service Saskatoon
4.  Materials :  Materials used in the rotor of the brake also determines the lifespan of the brakes. Carbon-ceramic brakes lasts longer than conventional metal brakes.