Used of human failings:

nobody's perfect

All people have faults or make mistakes. Used as a means of consolation or of mitigating judgment or criticism against someone or something.

• A: "I'm sorry I screwed up our presentation today." B: "Hey, nobody's perfect. It's not the end of the world or anything."
• Nobody's perfect, so I try not to be too judgmental of other people.

[Farlex Dictionary of Idioms{sic}]

Used of human failings:

Nobody's perfect

All people have faults or make mistakes. Used as a means of consolation or of mitigating judgment or criticism against someone or something.

• A: "I'm sorry I screwed up our presentation today." B: "Hey, nobody's perfect. It's not the end of the world or anything."
• Nobody's perfect, so I try not to be too judgmental of other people.

[Farlex Dictionary of Idioms{sic}]

We all make the occasional mistake.

• However we all make the occasional mistake and it is not something to beat yourself up over if you get an order wrong.

[Amazon Sales Forum]

These 'fixed phrases' (actually sentences) are not idioms as they are totally transparent (and sentences). They aren't really proverbs either. I'd class them as aphorisms: pithy observations.