There are endless supplies of cards listed on ebay that will never sell for the asking price. If the owner is so inclined to sell, they will eventually adjust their price. If they don't, maybe they just don't care enough to sell it at all.
I have been watching a Panini auto card for months. The seller listed it for $150 OBO. I offered $57, as most were selling in the same price range, many for less. I felt it was a very generous offer. I had landed some similar cards as low as $35. He passed. I offered the same price a few months later and he passed again. He had one other offer, which expired.
Since he listed his, several have sold for less than the $57 offer I made, but his price still remains at $150 OBO. He can keep it and he probably will, as I have not seen one sell for much more than $60.
I'll never know why he expects so much for his, but I can bet that his mind won't be changed. On the other hand, there are more than enough sellers who start everything at 99 cents and let the market do it's thing and that is why there will always be bargains!