A person died and went to hell.
The demon who took charge of him told him that there were many rooms in hell, and that he could choose which one he wanted to spend eternity in. But once he passed a room, he could not go back.
The first room had a concrete floor. People were inside, standing on their heads.
"I'll pass this one up," he said.
The second room had a dirt floor, ditto.
"Nope", he said.
The third room was ankle-deep in mud. But the people inside were standing around laughing and talking and sipping coffee.
"This is the room for me!" the person said.
Right then another demon came into the room and said, "All right, coffee break's over! Back on your heads!"
I'm telling this because every now and then you hear somebody say "coffee break's over, back on your heads", and it occurs to me that eventually this will become a saying that no one knows the reason for. And that will be a shame.