[tomxor]

Yeah, the irony... that completely mislead me as to the tone of this blog. I assumed it was going to be about psychology of better UI/UX, not disdain for bad UX and trickery.

I assume the janitor sign worked because people subconsciously will ignore things that have the appearance of being permanent while operating in the context of something familiar... the janitor sign appearance implied a recent and temporary change.

Conversely if the person has never been to that building/elevator before they would probably be equally likely to notice either sign.

[radley]

A hasty "Out of service" works instantly because we (as Americans?) are conditioned to expect to see that when something is broken, just like a stop sign.

The longer note looked like a notice, which people tend to ignore — particularly if they're in a rush or frustrated.