Auctions run into a lot of problems.. far more than the fixed price BIN listings here do. So what you encounter isn't unusual.
Buyers don't pay for what they won for a whole lot of reasons. Sometimes, they've seen the item and placed their minimum bid immediately, and then are never outbid, and have totally forgot about the item. And when the winning invoice comes in, they never even see it because they're not in touch with their eBay account for another 5 weeks.
Or, they changed their mind. It was fun bidding, but in the end.. by the time the auction was actually over and they found out they'd won.. the impulse was gone, and they'd cooled to the item, and now don't want it after all.
Some buyers will bid on two (and even more) auctions for the same thing, just to hedge their bets, and then only pay for the one that ended up going for the lowest price. The other(s) remain unpaid.
Some winners are kids, playing on their computers, having fun running up auctions with NO intention of paying for what they win. Rarely it's another seller who is trying to get YOUR item off the market, so that HIS item is the only one currently shown for sale, so that maybe that will help his item sell now.
Shoppers just change their minds. We see the items they leave behind in their shopping carts, ask the checkout girl to set back under her counter as they've changed their mind, we see things set on a shelf somewhere it doesn't belong, but it's out of their cart... etc.
All you can do is send the invoices out, and then open Unpaid Item cases to get your selling FVFs back, etc. Put the buyer on your BBL if you want. Sorry this happens to you. I don't do auctions much because I think they are more trouble than they're worth!!!
