Foreign middle aged man who can't speak the language very good in an environment where native language is important - not a good culture fit.
Female 25 year old in a group of 50 year old men who mostly wants to relax at work and are a bit awkward around young women - bad culture fit.
Very outspoken social person who enjoys partying in the middle of senior bank personalities who are extremely detail oriented and introverted - bad culture fit.
Just saying there is a lot of bad culture fits. It can be age, gender, race, personality and even appearance. Bad culture fit is everywhere. It's just not something we talk about very openly because it's not socially accepted. So we hide it under other reasons.