system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Does the Imperial Military allow you to leave/retire peacefully?
gpt
Yeah. It's got nothing to do with being nice, and is entirely a matter of practicality. Eventually, the enlisted men are gonna get too old for grunt work, and any officer who can't earn, beg, borrow or steal a higher rank should be cleared out to give someone else a shot. Keeping someone past the point of usefulness is a burden, in the long run.

That said, you stay or go at the Empire's convience, not your own; if you are in a specialty that is short-handed, or the higher-ups question your motives for leaving, an Imperial Stop-Loss Order could be used to keep a man or officer around indefinitely. And during times of war/rebellion (read: the entire history of the Empire), it pretty much means your career ends when the Empire says it ends, or you die.