A friend lives in a dormitory. They have a fire alert system there - a loudspeaker in each room, sometimes report important announcements and check. He tells me today:
The masterpiece! I sit on the internet, and suddenly I hear an announcement from the dynamic alert: "Dear residents! Anyone who does not have an alert speaker, please contact the 3rd floor with a request to repair it!"
HH: And they really believe that someone will turn.