Meaning of the word "a fish always rots from the head down" in English

What does "a fish always rots from the head down" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

a fish always rots from the head down

US /ə fɪʃ ˈɔːlweɪz rɑːts frəm ðə hed daʊn/
UK /ə fɪʃ ˈɔːlweɪz rɒts frəm ðə hed daʊn/
"a fish always rots from the head down" picture

Idiom

used to say that if an organization or government fails, it is because of its leaders

Example:
The company's collapse was inevitable because a fish always rots from the head down.
Corruption in the department is rampant; clearly, a fish always rots from the head down.