I'm not an Ebay person, but I have lots of friends who are, and I've certainly read enough about the philosophy to get the idea. You go on looking for something, and then you watch the bidding over a period of time. In the end, if you want to get something, you pay the price that it takes to get it. If you can't stand watching others bid, you take the "Buy It Now" option.
There's a real estate theory along the same lines. When a house is listed, potential buyers look, and note the price. They often sit back and watch the action, sometimes bidding, but often waiting. If they really, really want just that house, they will go in early and strong, and close the deal. If not, they wait and see. At the end of their search, if that's the house they want, they need to outbid others to get it.
The idea is that things will sell, in most cases, for what they're worth. There may be times when sellers get lucky, or buyers do, because of circumstances not created by them, but by the other party. Most of the time, property goes for its fair value, because bidders will eventually come in and pay what they know it's worth. The moral? It's not the listing price, it's the inherent value. Put your property on low, and let buyers bid it up. Just as in Ebay, if you can create a feeding frenzy, you will get more, and much more quickly, than if you list it too high.