I am inexperienced when it comes to travel savvy but I noticed something today that was unexpected. When I was looking into changing a United flight after the initial 24 hours, it seems one that one of the options is to change it into the same flight, but a refundable fare. If that is the case, what is to stop someone from changing to a refundable fare and then just canceling the ticket for a full refund? I must be missing something here.