First rule of
DVC: understand inventory. There are two different inventories of DVC properties. One is what is available through Member Services on points and the other is only available for cash through Disney Reservation Center. What you see at DRC is usually owned by DVC and not by members, or traded by members for non-DVC Disney stays (like they wanted to go on the
DCL and used points to do that). So DVC takes the accomodations that represents the members non-DVC Disney stay and turns that over to DRC to sell to pay for the non-DVC Disney vacation. They don't give us DCL staterooms for points. They have to be paid. Someone books that stay for cash via DRC and the money goes to DVC (less some fees) to pay for that cruise. And since the villa has already been booked using points (to trade to DCL), that villa cannot be reserved on points again. And if it stays empty, it stays empty.
Also, as new resorts are built and unsold inventory remains, that, too, is turned over to DRC to sell. And then DVC owns a small percentage of the villas to use when they need to take villas out for maintenance and such. If they don't need to take them out of service, they get sold for cash.
The only inventory that is available for a points stay is the inventory owned by members that has not already been traded for a non-DVC Disney vacation.