What good's a fireproof safe if the only guy who could enter the combination has retired?

How to say “What good's a fireproof safe if the only guy who could enter the combination has retired?” in French

In French

À quoi ça sert, un coffre-fort résistant au feu, si le seul qui savait composer la combinaison est parti à la retraite ?

What good's a fireproof safe if the only guy who could enter the combination has retired? in other languages