Steering Wheels, Wheel Skins

[cpurick]

I'm buying a 2001 Explorer Sport. Nearly every vehicle I've seen has some kind of wheel skin on the steering wheel. Why is this? Is there some sort of decomposition problem with the original steering wheel material?

 

[MountaineerGreen]

Most are leather wrapped, many people tend to "ring" the wheel, twisting and eventually loosening the leather to a point that it becomes annoying. Mine started to show a little wear, so I covered it with a slip on cover.