How would you describe a credit default swap to a builder?

And the answer was:

The candidate said: "I starting out by saying something like-it's basically a contract where the buyer of the swap makes regular payments to the seller and then in the case of a particular event happening the seller pays a predetermined sum to the buyer-but was stopped half way through for being too complicated (actual response was 'whooooosh' and gesturing with his hand that my answer went over his head) and told to try again. So I said it's basically the same as car insurance and was told it was the answer he was looking for."

Additional information

This was allegedly asked during an interview for a credit derivatives trade support role at JP Morgan. The candidate was offered the job.