Somebody's/something's days are numbered sentence
Meaning somebody or something will not survive, work or succeed for much longer.
Peter knew his days were numbered. That's why he spent all his time with his family.
My laptop's days are numbered. It keeps turning off by itself while I am working.
The doctors have told my family to be prepared because my grandma's days are numbered.
To quit; to give up, stop doing something because you know that you cannot succeed; admit defeat
The inexplicable or concealed place or state indicates the afterlife.
a joke, idea, or suggestion falls flat, meaning that it does not achieve the intended effect.
To begin to decline or deteriorate decline; to get worse very quickly
The first record of this phrase is believed to be written by Reginald Scot, in his The Discoverie of Witchcraft, 1584. Moreover, the expression is supposed to be related to the Bible or Shakespeare.
A humorous way of saying that what one has said is just what they acknowledge and may not be entirely accurate
Mike: Have you returned from your vacation on the beach? Your skin seems to get tanned.
Jenny: My skin is always dark. That's my story and I'm sticking to it!