Comment by the_gastropod

Yep. Therein lies the rub. eBay inserts themselves as the middle-man here. But they take 0 responsibility for assessing disputes if a buyer claims an item was not as described. They just arbitrarily refund buyers, and automatically pay for the shipping fees from the sellers' connected bank accounts. To make matters worse, as a seller, as far as I know, you can't limit how much the buyer can spend on shipping. So, e.g., if someone on the other side of the planet buys something from you, pays for shipping, then says "item not as described", you're going to be on the hook for a large sum. I guess this happens rarely enough for most big sellers that it's worth continuing to use ebay. But for average schmo use-cases (like selling old household goods), it's a ridiculous risk.