This happens in Germany.
Work culture doesn’t fit my personality: I don’t talk much, I keep to myself, I simply want to do my job and go home, I separate my personal life from work, my colleagues are full fledged gossips, ignore the duties that need to be done and then expect me to help them when they are late. I don’t have patience for that crap anymore.
Due to internal regulations, I have to stay on the unit for 4 weeks after sending my notice. Answering honestly the question of why I’m quitting would ensure that they yell at me and bully me, and I don’t want to experience that again. Even saying ‘it’s none of your business’ ensures that they feel insulted and start yelling. I have decided I don’t have patience for people like that anymore.
So, what do I say?
It isn’t any of their business unless you want it to be so just be vague as hell. “I got another offer that is a good opportunity.” “I’ve decided to pursue other opportunities.” They’ll obviously ask questions and you can just remain vague. “I would rather not discuss specific details of my new job.”
Or if you don’t mind them speculating behind your back you can say as something like “I’ve decided to move on for personal reasons.” Just leave it at that and let them sit there and wonder. Is a family member sick and needs care? Are you sick? Did you get a different job? Do you hate everyone? Are you going to prison? Who knows because you aren’t telling them.