In the Spring and Autumn Period (春秋时期,770-476 BC), there was a beauty in the State of Yue called Xishi (西施).
She often suffered from pains in her chest, and so she would often walk around doubled over and with her brows knitted.
There was an ugly girl in the village called Dongshi who envied Xishi.
Striving to emulate Xishi, she imitated her stoop, knitting her brows at the same time.
She thought that this made her elegant, but in fact, it only made her more ugly.
Later, this idiom came to be used to indicate improper imitation t阿诺果门内hat produces the reverse effect.