What is the origin of waiting for the other shoe to drop?

Answer 1

It means waiting for something bad to happen which you are expecting. It comes from a famous music hall joke about a man who is woken by the drunk upstairs dropping his shoe. He can't get back to sleep because he is waiting for the second crash on the ceiling. Eventually he shouts upstairs "For Heavens sake, drop the other shoe!"
The basic expression came from apartment living. A person living in an apartment underneath another apartment would hear a person take off a shoe and drop it on the floor and then wait for the other shoe to drop. Then the thump of the other shoe would occur. Then the person in the bottom apartment could continue reading or whatever without interruption. However, it became a useful expression if two irritating events frequently occur together. If someone says, "Why didn't you get back to work?" Rather than say, "Any time that guy comes down the hall pushing that noisy cart that goes clang, clang, clang, with that horrible sound, and disturbs everyone, a second one comes right afterward with its own irritating racket," you can say, "I'm waiting for the other shoe to drop."

Answer 2

It goes back to the days when wooden buildings had thin ceilings and you could near nearly everything that happened upstairs. When someone took off a shoe and dropped it on the floor, it made a clunk which might startle you -- especially if you were trying to sleep. Then you had to wait for the other shoe to drop.

It has come to mean waiting for what comes next, if it seems pretty inevitable.

Answer 3

The expression comes from the sound of someone taking off his shoes in the room above you. They take the first shoe off and BOOM it hits the floor, and then . . . Basically you are left waiting, expecting a second BOOM when the second shoe hits the floor.

Metaphorically, it applies to any series of events which is not complete until the last part of the sequence has taken place. If there is an unexpected hesitation before the last step in the sequence, those people waiting for the whole series to be done are "waiting for the other shoe to drop."

If someone tries to respond prematurely to such a sequence, another might tell him to "wait until the other shoe drops".

You're at a meeting with the boss and your co-workers John, Ernie and Francine. The boss has the results of your performance assessments. He tells you you've done well. He tells John he's done well. He tells Francine she's done well. And . . .

Now is not the time to interrupt him. Wait for the other shoe to drop.