Once upon a time, there was a man who kept a flock of sheep. One morning, he went out to herd sheep and found that one was missing. There was a hole in the sheepfold. At night, the wolf got into the hole and took the sheep away.
Neighbors advised him: "Hurry up and fix the sheepfold and plug that hole!"
He said, "Why build a sheepfold when all the sheep are lost?" Didn't take the neighbor's advice.
The next morning, he will go out to herd sheep. When he was looking in the sheepfold, he found another sheep missing. It turned out that the wolf got in from the hole again and took the sheep away.
He regretted not listening to his neighbor's advice, so he quickly blocked the hole and mended the sheepfold. Since then, his sheep have never been carried by wolves.
The big story is: because the sheepfold is empty, it is not too late to repair the sheepfold after the sheep have been taken away by the wolf. Figuratively speaking, finding a way to remedy the problem can prevent further losses.
This article is selected from The Warring States Policy Chu Ce IV. It explained: if the sheep are lost, mend the sheepfold and the remaining sheep will not be lost again. If you make a mistake and correct it immediately, you can reduce it. If you make a mistake and take remedial measures in time, you can avoid greater losses.
For reference.