An escalator can never break, it can only become stairs. You would never see an “Escalator Temporarily Out Of Order” sign, just “Escalator Temporarily Stairs”. Sorry for the convenience. We apologize for the fact that you can still get up there.
The Librarian (Discworld) (Wikipedia)The Librarian appeared in the second novel of the series, The Light Fantastic, where he was transformed into an orang-utan. This had certain advantages for a librarian, such as being able to use his hands and feet for re-shelving books. The other wizards have gradually become used to the situation, to the extent that, from Night Watch: “if someone ever reported that there was an orang-utan in the Library, the wizards would probably go and ask the Librarian if he’d seen it.”