Is permanent residency really permanent? As far as I'm aware, only New Zealand PR is really permanent. For Canada and Taiwan, I know that if I leave, I'd lose i

Is permanent residency really permanent? As far as I'm aware, only New Zealand PR is really permanent. For Canada and Taiwan, I know that if I leave, I'd lose it. So the only unconditional right to return is citizenship, and naturalising to become Japanese is really hard from what I've heard.