What is wrong with the pot calling the kettle black?

The implied term is that the pot is insulting the kettle by calling it “black”.

It’s as though the alcoholic were saying “You’re nothing but a damned dirty alcoholic”, which would would effectively start a Pee-Wee-esque “I know you are but what am I?” argument.

I don’t think that there is necessarily anything wrong with the pot calling the kettle black.
Just as you said, it often, “takes one to know one”.

You have a point. Generally when I hear that saying used, however, the pot is calling the kettle black while somehow thinking, or outright denying, that they themselves are the same way – thus the pot is somehow thinking they’re better than the kettle – even though they aren’t in reality.

Yes @Seek_Kolinahr, and @DrasticDreamer I agree, with what you say but, it doesn’t always have to the case of an insult. Sometimes, it’s an affirmation.

In that case, the idiom does not fit the situation.

@Seek_Kolinahr @DrasticDreamer Great points. Thanks. It’s used to shut people up all the time in political debate. One side charges that the other is only for/against measure X because lobbyists are making it worth their while. The opposition responds, your leader took over $1 million from lobbyists. Maybe so, but that has nothing on earth to do with the merits of measure X or whether the speaker’s position on it is bought and paid for.

@wilma Thanks.

Oh, those racist pots!

@MissA Ha! Sorry, the pot calling the kettle African American.