The service life of a motor mainly depends on the bearings, magnets and coils/winding. Under normal service conditions, there is a slim chance that magnets or coils get damaged, and thus the service life of a motor lies in the wearing part: bearings. But luckily, bearings are replaceable. It is recommended that the bearings to be replaced after 800-1000h even if they are not damaged. The service life of a motor can be 1 year to several years under proper use and maintenance.