Warranties and insurance don't guarantee anything. Companies that offer those things make their money by denying claims. Insurance companies deny claims when they think they can get away with it all the time.
tldr; there is no such thing as an absolute guarantee
The only thing you can probably get out of a “guarantee” is a piece of paper you can submit as evidence in a court of law. How much you value that depends a lot on what it says and who gave it to you.
tldr; there is no such thing as an absolute guarantee