Why does the oil-bearing cooling fan not have a long life?

When we mention oil-bearing cooling fans, the first thought is that this is the most common fan with a short lifespan. What caused it? When we understand the oil-bearing cooling fan, the cooling fan manufacturers who advocate that the life of the oil-bearing fan can be used for 3 or 5 years are actually very clear. There are two main reasons for its short life: 1. The cooling fan that runs in a high temperature environment for a long time will cause the lubricating oil to be dried. After the oil of the oil-containing cooling fan is dry, it will directly rub the bearing and the shaft core. The sound becomes louder. Finally, it won’t turn. 2. Our cooling fans are generally in a dusty environment. After long-term use, the dust is sucked into the inner hole of the bearing, and the more it collects, the more it gets stuck.