The fact that FF miles don't earn interest and are subject to devaluation as what led me to adopt a "policy" about how large to allow my balance to grow several years ago. I've taken many, many free tickets from my account since then -- much to the delight of family and friends! Rather than hoarding miles, it encourages a little more aggressive account management and assures that value is constantly being received. Life itself is temporary! Banking on things to remain the same in something like frequent flyer programs is a recipe for disappointment, IMHO. As a previous poster alluded to, you may be dealing with a more perishable commodity than you realize.