If the infected user hasn't paid up by the time the clock elapses, the key is thrown away and the files are essentially lost forever.
If the user doesn't have backups, then his files are eventually going to be lost forever, for any one of a number of reasons, most of which are far more likely than being bit by a ransom virus.
You don’t understand. I was hit with this and it may sink my company. I have backups galore, all attached to the network, NAS, this stupid thing got them all. I will have thousands of man hours of labor just to have information to do my taxes.
These people need to be shot.