@Graeme M Currently, the United States constitution sets a limit of 2 terms for the President. Most other elected officials can stay in office so long as they keep getting re-elected. I'm a little embarrassed to admit this article had some things I wasn't aware of (*+* WARNING: click at your own risk):
en.wikipedia.org
I think president Franklin Delano Roosevelt was the only one to ever serve more than two terms. Donald Trump is the first president in my country's history to be re-elected for his second term
after losing an election at the end of his first term- but as things stand, he's out for good once this term ends. (Or perhaps sooner than that- he's the only president to have been impeached twice as it is, and he can be impeached a third time if he gives enough people a reason to do that.) I'm not currently worried about some sort of revolution happening, with Trump becoming dictator; I hope I'm not being naive.
(*+* : I usually avoid using Wikipedia because they keep bugging me for a donation when I access their website, and I think they
should get something for their work- but I wanted to give their website credit since I got this info there. And I don't have a PayPal account.)