I had a job interview yesterday where they asked what the only scenario where a one-time pad can be broken would be, my answer to which was "when the key distribution process is not secure enough".

They praised my answer, but they asked me another question: Why would you even use a one-time pad if the key distribution is 100% secure? Why not simply send the plain-text message since you are sure that distribution is 100% secure?

What is the correct answer to that question?

You can distribute the key now and send the message later.

Suppose you are a spy sent on a mission behind enemy lines. You take the key with you (secure distribution) and when you discover a secret you can securely send it using the One-Time pad.
