Is it true that what goes up must come down?

Is it true that what goes up must come down?
 
Probably. So let’s recognize guardrail and its battle against the force of gravity.
 
Helping to keep what is on your deck, balcony, and stairs from coming down the wrong way.
 
 
Pictured: Deck and stair ornamental steel safety railings at Crystal Bay (Washoe County.)