Why it is problematic for a cream to get spread on the outside of a jar?

Medicinal and cosmetic creams are often intended for specific uses and specific parts of the body. Unless protective gloves are worn, handling the jar with cream outside will result in the cream on the hands where it may not be desired.

A cream can make the outside of the jar slippery, more difficult to handle, and increase the risk of the jar slipping, falling and breaking, resulting in the cream spreading to places where it was not intended to be.