Sometimes I watch something (usually a Buy It Now) that is overpriced. If it doesn’t sell and is re-listed, it will often be at a lower price.
However, I have seen at least two instances where the seller RAISED the price when it was re-listed. A marketing strategy that I don’t quite understand.
Sometimes sellers will offer a discount on a BIN listing, so buyers watch BIN listings waiting hopefully for a discount. As a seller, I never give discounts because my selling account doesn’t offer it, and I market research beforehand and price stuff at market, so my watchers are probably disappointed.
I’m somewhat hesitant to place anything I’m seriously interested in buying in my watch list, just sniping it instead, because Ebay changed it so that sellers can see how many Ebayers are watching any particular listing.