"I agree that this is all about culture." Not just about culture but also legal. In the US, most states have employment at-will which means employers can fire

"I agree that this is all about culture." Not just about culture but also legal. In the US, most states have employment at-will which means employers can fire an employee anytime without any notice and vice versa. Of course, exceptions are there for things like discrimination but you still have to prove it. In the US, a lot of states do not require you to provide any benefit to your employees other than a salary if you are a small enough business. In many parts of the world including Asia/Europe, employers cannot just fire someone (with exceptions in extreme circumstances like a crime) and employees cannot leave immediately either. 90 days advance notice is very common.