yī​kē​lǎo​shǔ​shǐ​huài​le​yī​guō​tāng

one bad apple spoils the whole bunch

一颗老鼠屎坏了一锅汤 一顆老鼠屎壞了一鍋湯 yī​kē​lǎo​shǔ​shǐ​huài​le​yī​guō​tāng
one bad apple spoils the whole bunch
One bad person or thing ruins everything else, like a single piece of rat droppings spoiling an entire pot of soup.

Cross-References

See