Engineering360: "Video: What causes quicker belt wear?"

Check the bearings on all items driven by the belt. Excessive friction poses a greater tensile load on the belt. Wobbly bearings may intermittently lock up, which would also be hard on the belt. Make sure the belt tension is within specifications.

In a combustion engine application, if the belt is prematurely cracking, check the alternator for heavy sparking due to overloading or worn brushes - the cracks may be ozone damage. Also verify that there is adequate airflow through the engine compartment to prevent overheating. In particular, inspect the front of the radiator for debris clogs or mashed-over cooling fins. These steps would be in addition to checking for mechanical issues.