That's exactly the reason why the culture fit is not clearly defined in companies. Any newcomer brings a potential challenge to status quo. The 'culture' is in

That's exactly the reason why the culture fit is not clearly defined in companies. Any newcomer brings a potential challenge to status quo. The 'culture' is in fact may be quite the opposite to the proclaimed values. This may not be visible(any longer) to those that 'fit', yet may be quite apparent to someone new. Hiring manager may not even realize what 'culture' has been fostered. Team dynamics is a tricky thing. I doubt that any team would scout on purpose for assholes, yet many stable teams may keep one/some. Same at the other end. As long as the rotation is not high, the mix is the 'culture'. That's why 'culture fit' is often invoked as a guise for something else short of discriminating answer.