So I was waiting for the elevator at the Jerusalem train station. Due to the mountain topography, the trains stop 80 meters below street level, so the elevator is a must!
And I see next to the elevator button the sign in the left photo below. Sounds like a quantum physics paradox – perhaps you can enter and not enter at the same time?
Fortunately the sign at the door to the adjacent elevator has the remains of a red sticker, so it’s possible to reconstruct the evolutionary path from well-intentioned signage to useless confusion. Clearly the signs originally had a red circle at the top and a green one at the bottom; this is a legend for a physical “traffic light” above each door, which signals whether one should go in or not (pretty silly, given that you can see whether the door is open or closed, but anyway).
What caused this mess is the design decision to print the text on the sign, and to add the colored circles as stickers on top of it – giving each element different resistance to erosion. It is also yet another example for the deplorable incursion of stickers into public signage, as discussed here…