What’s the origin of the phrase “waiting for the other shoe to drop”?
a joke where a man was always complaining that the neighbor upstairs dropped his shoes when he took them off every night and so woke him up. He complained to the neighbor who, that night dropped the first shoe because he forgot. But then he remembered and put the second one down softly… but the downstairs neighbor spent the night awake waiting for the next shoe to drop.
The phrase is used to mean someone is waiting for something unpleasant which should logically follow what has already happened.
Thanks sailor. I’ve asked many people that question, to no avail. Should’ve come here first. 
I think along the same lines there was a Seasame Street Bert & Ernie skit where Bert was waiting for the guy upstairs to drop his second shoe so he could fall asleep. After much time the second shoe drops, Bert says “Finally!” and prepares to nod off, only to hear a THIRD shoe thud to the floor. Hilarity ensues! Ah, can’t beat the classics. 