For Off & Away newbies, the way it works is you buy bids to participate in an auction for ultra cheap, but nice hotels. It's a "loss leader" of sorts. If you win the auction, you just got an incredible deal. If you lose, you can apply the $'s you spent on bids to your next hotel purchase. So you have nothing to lose and a lot to gain.
Warning, these auctions get really addictive. I spent 45 minutes in a Subway in Indianapolis, bidding like crazy against another person. Not easy to pull yourself away!
P.S. for you psychobiology nerds out there, Off & Away is an application of one of Cialdini's Principles of Persuasion - Committment. I highly recommend you read this book