Most all garage door parts lifespan are measured in cycles (Cycle=door opening and closing once.) Starting with the basic grade of roller with no ball bearings. These type of roller is rated for about 10,000 cycles. usually the wheel part is plastic. So lets do a little math. If you only open and close your door twice a day thats 2 cycles per day. Thats 5,000 days divided by 365 days a year thats a little less than 14 years of lifespan. The next grade of rollers have 11 ball bearings and a solid steel wheel or a steel wheel with a nylon tire. The ball bearings will give the roller about 5,000 more cycles than the rollers without ball bearings 15,000 total. This would work out to about 20 ½  years of lifespan if you opened and closed your door twice a day.

Commercial grade rollers

Commercial grade rollers have much more lifespan than your basic residential rollers. Commercial rollers can have a rating up to 100,000 cycles. As far as everything in between the difference will consist of how many ball bearings the roller has to the stem being of hardened or tempered steel. The reason for more durability in commercial rollers is the extra weight involved plus replacement of the rollers can be expensive for a door with 20 rollers. The places where you might find rollers with lots of durability is in emergency vehicle garages like fire houses and rescue vehicles. These doors will need to be the most reliable over any other kind of door. Usually contractors do not spare any expense when it comes to durability and reliability. Especially when you have high wind locations that need the extra strength to keep rollers from being beat up by a garage door flapping around in high winds. If a low grade roller is used in a high wind area the door will slightly move back and forth and cause rollers to prematurely wear out. There is also a grade of roller that are called car wash rollers. These rollers have a sealed bearing which means the bearings are sealed from the elements like water. They are also sealed in a material called UHMW. Its basicly water resistant coating on the wheel of the roller. There is a roller for all garage door applications.