What is the typical consequence of insufficient lubrication in bearings?

Insufficient lubrication in bearings typically leads to increased heat generation. Lubrication serves several critical functions, including reducing friction between moving parts, dissipating heat, and preventing wear. When there isn't enough lubricant, friction between the bearing surfaces increases, which in turn generates more heat due to the excessive surface contact and movement. This excessive heat can lead to further issues such as lubrication breakdown, premature wear, and ultimately a failure of the bearing system.

The other options presented do not accurately reflect the consequences of insufficient lubrication. Enhanced rotational speed is unlikely because increased friction typically hampers smooth movement, making it harder for the components to rotate freely. Decreased wear resistance would be a consequence of insufficient lubrication, but it is specifically related to the failure of lubricant to protect against wear, rather than a direct outcome. Prolonged bearing life is contrary to what happens with inadequate lubrication, as the bearing is more prone to failure and damage when not properly lubricated.