If sellers get a neutral or negative feedback from a buyer, it seriously affects their credibility and the sellers would find themselves ignored. In really bad cases of misrepresentation, eBay will refund the buyers from the insurance all sellers must buy. The sellers can then get ejected, if I'm not wrong.
Two personal examples. I once bought a piece of costume jewellery from someone in HK. An entire month passed and it still hadn't arrived (partly because it was shipped from China). I wrote to the seller asking about it. Within 5 minutes, he replied to my email saying he would send a replacement. He also requested that if two should arrive later, that I send the extra one back. Two did arrive within a week of the exchange and I sent one back.
Another example. I bought a camera lens cap from someone in Israel and it didn't fit (through no fault of his). I asked to try another one and he sent it immediately, only asking that I sent back the earlier one. He also said that if the second one didn't fit, to send it back and he would refund me. It did not but I used it for something else.
Can share what you can ask in addition to the product being sold that the eller will bend over backwards to please you?
Seriously, I thought if buyer ok with price and the terms, either buyer buy or just ignore?