画蛇添足
huà shé tiān zúHe finished first, so he kept drawing. The idiom for ruining a good thing by overdoing it.
The Story · 故事 gùshi
A group of retainers in the state of Chu were given a single jug of wine to share among them. There was not enough for everyone to drink properly, so they devised a contest. Each man would draw a snake on the ground. Whoever finished first would win the wine outright.
One man finished his snake well before the others. He picked up the jug, looked around at the still-bent backs of his friends, and said: "I have time to spare. I will give my snake legs." He took up his stick and began adding feet to his drawing.
Another man finished while the first was still drawing. He snatched the jug from beside the first man's hand and drank, saying: "A snake has no legs. How can you give it legs? What you have drawn is not a snake. The wine is mine."
The story comes from the 战国策 (Zhànguó Cè, "Strategies of the Warring States"), a late Warring States compilation of political anecdotes assembled in its received form by Liú Xiàng in the first century BCE. The original parable was political — used by an envoy to persuade a Chu general against attacking Qi, on the grounds that the general had already won enough and any further victory would only undo what he had achieved.
Usage · 用法 yòngfǎ
The idiom describes any case where a person, having done something well, keeps going past the point where it was good. The legs do not improve the snake. They make it not-a-snake. The destruction is not because the work was bad but because the work was finished and the worker would not stop.
A clean piece of writing ruined by an extra explanatory paragraph. A solved business problem reopened by a meeting that was supposed to "tighten" the solution. A negotiation already won, then lost by a final demand. A novice cook seasoning a dish that did not need it. The Chinese phrase carries a specific embarrassment — the doer was the one who undid their own success.
这篇文章本来很好，你最后加的那段就是画蛇添足。(Zhè piān wénzhāng běnlái hěn hǎo, nǐ zuìhòu jiā de nà duàn jiù shì huà shé tiān zú.) — This article was already good. The paragraph you added at the end is drawing legs on a snake.
Character Analysis · 字解 zìjiě
To draw, to paint. Pictograph of a hand holding a brush above a field, originally meaning to mark out boundaries. The traditional form 畫 shows the brush (聿) above 田 (field) more clearly. Compounds: 画家 (painter), 漫画 (manga), 计划 (plan, with 划 huá the same root).
Snake. The 虫 (chóng, "insect/reptile" radical) on the left tags it as a creeping creature; the right side 它 was originally a pictograph of a coiled snake itself, and is now a separate character meaning "it." So 蛇 is, etymologically, a snake-radical added to a snake-pictograph for clarity — a kind of redundancy the parable itself warns against.
To add, to append. The 氵 (water radical) on the left suggests adding liquid; the phonetic 忝 carries the sound. Used widely for additions of any kind: 添加 (add), 添麻烦 (cause trouble, literally "add trouble"). The connotation is often slightly negative — adding when nothing more was needed.
Foot, leg. Also "enough, sufficient" as an adjective: 足够 (zúgòu, sufficient). The double meaning is part of the idiom's quiet pun — by adding feet (足), the painter shows he did not understand 足 (enough). What was sufficient he made insufficient.