It's rude not to give notice when quitting a job.
Hannah has been working under a really tough boss for a while and has had enough of it.
Hannah wants to quit her job.
Hannah opens her email software and sends a resignation letter to her manager with two weeks notice.
Hannah walks into her manager's office and throws her ID badge on the desk and tells the manager she's out and quits.
Hannah's manager is sad to see her go but understands and gives Hannah a glowing reference.
The manager is stressed out and scrambles to find a replacement on short notice.