Micro Cooling Fan Why is there a case of rejection of oil?

"Micro Cooling Fan" We all know it's bearing and a few other parts that need oil for lubrication. Oil is the lubricant of our common, however, took part in this oil grade. High, medium and low grades of oil. Low-grade oil, it is relatively thin, pour out like water might be just a little yellow color, but also volatile. High-grade oil, viscous better, not susceptible to air to evaporate. Thus making it a longer life. "Micro Cooling Fan"  less lubricant is a fan of the quality of a relationship. Oil adds a fan in operation, it is possible to put the oil thrown out. Oil less of it, it will make the life of the fan will not reach 2W hours. Rejection of oil is divided into two kinds. One is dumped oil cooling fan page, one is thrown at oil cooling fan label.
The first rejection of oil, mainly oil too much. There is oil too thin.
The second rejection of oil, mainly because oil does not cover the rubber seal, but the seal is too little. Label itself is "Micro Cooling Fan" with a sticky, then you tear off the label, oil blocks also torn out. Did not pay attention when, after the label back then, there is the possibility of oil spills.