It depends.
Some ball bearings are open and should be lubricated
Some ball bearings are sealed with lube. These do not need to be lubed frequently.
Then there are the ceramic ball bearings which require little to no lube:
https://www.bocabearings.com/p...arings?ProductType=0
What good is lube when the ball bearing is being operated at 2000 F? However, I somehow suspect that most of you are not using a ball bearing that can cost up to $1500 (perhaps more) per ball bearing.