Buy where you won't be disappointed if you end up staying there.....
Many DVCers make their ressies at their home resort at the eleven month window. Then at seven, they see if where they want to stay is available. If you have a WDW home resort and are planning on going to Disney - you aren't too disappointed if you end up at your home resort of VWL instead of BCVs.
If you NEED to be a VWL in early December, BWV during the Food and Wine Festival or get a OKW Grand Villa, you'll want to make your home resort the place you want to stay. (Now you see why so many people have points at a lot of resorts).
Using this logic, its easy to see why a home resort of VB or HH might not be your best option if you want to have WDW vacations.