Hitting the brick wall right behind that sign would cause a much more serious injury than hitting the sign would. It's the same idea as those signs by bridges that say "if you hit this sign you will hit that bridge!"
Better a minor bump on the head than a concussion. Not that an escalator moves fast enough to cause a concussion but you get the idea.
It's warning that you could hit your head on something
This confuses me still
Hitting the brick wall right behind that sign would cause a much more serious injury than hitting the sign would. It's the same idea as those signs by bridges that say "if you hit this sign you will hit that bridge!"
Better a minor bump on the head than a concussion. Not that an escalator moves fast enough to cause a concussion but you get the idea.
It's warning that you could hit your head on something