You don't understand his point. He's saying, how do you know that the system hasn't acquired some sort of configuration/software/hardware degradation in the me

You don't understand his point. He's saying, how do you know that the system hasn't acquired some sort of configuration/software/hardware degradation in the meantime that only manifests on boot? If you don't regularly exercise/test a critical function, then you substantially increase your risk that the critical function will fail when you really do need it. Q: What's the worst time to find out your system won't boot? A: Right after it crashed. You are better off with scheduled maintenance periods where you can reboot the server and it isn't critical if it fails. That gives you a chance to correct anything on your terms rather than fire-fighting.