During the Chu dynasty, there was an aristocrat. After worshiping the ancestors, he gave a jug of libation to the servants who helped him.

The servants discussed among themselves and said: “Every servant would draw a snake on the ground. The man who finished first would drink the wine.”

One man finished very quickly. He was about to drink the wine. However, when he saw others were still busy drawing, he said in triumph: “I can add feet to my snake.”

However, before he finished drawing the feet, another man finished drawing a snake. That man grabbed the wine jar and said: “Who has ever seen a snake with feet? How do you add feet to it?” Then, he drank up the wine.

Thus, the man who added feet to the snake didn’t get the wine in the end. The idiom "画蛇添足" (Draw a snake and add feet to it) refers to spoiling things by doing something unnecessary.