Meaning of the word "a rotten apple spoils the whole barrel" in English

What does "a rotten apple spoils the whole barrel" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

a rotten apple spoils the whole barrel

US /ə ˈrɑː.tən ˈæp.əl spɔɪlz ðə hoʊl ˈbær.əl/
UK /ə ˈrɒt.ən ˈæp.əl spɔɪlz ðə həʊl ˈbær.əl/
"a rotten apple spoils the whole barrel" picture

Idiom

one bad person or thing can have a negative influence on all the others in a group

Example:
You should remove the troublemaker from the team immediately; a rotten apple spoils the whole barrel.
The manager fired the dishonest employee because a rotten apple spoils the whole barrel.