Explain the pun old skiers never die they just go downhill

“Old soldiers never die—they just fade away” is an old saying that was popularized by General Douglas MacArthur (1880-1964) in his farewell address to Congress on April 19, 1951. Many parodies of the saying have been made.
“Old skiers never die—they just go downhill” is a jocular one-line saying that has been printed on many posters and T-shirts. The line has been cited since at least 1973; in 1975, the saying was advertised on a bumper sticker in Ski magazine.

The skier when down hill like he failed horribly if you want to have an explanation i am here because why the heck not 

The answer is 2) to show the depth of the colonists’ commitment to independence