Another unsung nicety related to this one is that you can fully update your system but only start using it once you reboot. Too many times I updated the kernel on Arch only to find everything stopped working until I rebooted, hence why routine updates can just be done automatically with no issues to the user.
I found out not long ago that I can’t donate blood in the US because I’m British and lived here during the 1990’s so could theoretically be carrying mad cow disease.