As a maintenance mechanic/millwright or reliability engineer, you may need change your job title to Maintenance Detective.
Pictured below are two felt roll bearings from a paper machine. They were changed out due to high vibration readings found during the vibration route. Both had been in operation for a year, too short of a lifespan in this application. What do you see when studying the bearings closer? They are spherical roller bearings, typical in this application for high radial loads, axial loads and misalignment. They are grease lubricated based on the holes in the outer race. The bearings have significant amount of watermarks on rollers and the outer rings..
This is a good start for some detective work through an informal Root Cause Problem Elimination (RCPE). The watermarks are probably the cause of the bearing failure. The question is, "How-Can the moisture enter the bearings and cause corrosion?"