foolproof vs fullproof
foolproof
Definitions
adjective
- not liable to failure
verb
- proof against human misuse or error
Examples
Virtually foolproof to use, it flattering.
Fair warning: The site is by no means complete or foolproof, so you should always cross-check by going to the source.
I don't believe there's any such thing as a foolproof scheme for making money.
