A paper A-frame sign on an escalator, with an iconic representation of a Myki card being swiped, an X to suggest it's the wrong thing to do, and the instruction: "Don't swipe."

Source: Flagstaff railway station elevator, Melbourne.

Because Melbourne’s new “Myki” smartcard for transit has an appreciable (and inexplicable) delay, commuters are being urged not to swipe, tap or wave (as they may be used to doing with every other smartcard they’ve ever used.)

The spin machine attributes the problem to user behaviour, and has resorted to the age-old trick of “fixing” the problem in the instructions. I think of the sign as a kind of in-advertisement, or an unstruction.