[prennert]

Is a roof you have to redo every 20 years, or a paint that only lasts 10 years faulty? Is a car that needs brakes replaced every X thousand kilometers faulty?

It is only faulty if it does not run according to spec, or if you it run outside the spec.

[hef19898]

Exactly. If the manual says "reboot every 51 hours", you do just that and all is fine. If you have to reboot every, say, 25 hours, something is broken.