Final answer:
Avoiding stopping on a hill while towing a trailer in slippery conditions is advised to prevent loss of traction during the attempt to start moving uphill again. More friction is desirable in icy road conditions and in sports equipment for better control.
Step-by-step explanation:
"Avoid stopping on a hill" is good advice for a Jeep® driver towing a trailer in slippery conditions primarily because it prevents loss of traction when starting again uphill. When attempting to start on a hill, particularly in slippery conditions, the tires' capability to grip the road is compromised. This can lead to wheel spinning, which could then lead to potential skidding or even becoming stuck. It's important that drivers choose tires that create more friction with icy roads compared to summer tires to improve traction during winter driving. An example where more friction is desirable is in sporting equipment, such as the grips of a baseball bat or gym shoes that need to provide greater control and minimize slipping during performance.