Years ago, I used Ebay to help build my model horse collection. I was always a buyer, never sold anything. If you've never used Ebay, there is a system of leaving feedback to rate the buyers/sellers you work with. So as a buyer, you bid, and if you win, you promptly pay for the item at which time the seller promptly ships the item. Then, if you are happy with the service and the item you leave positive feedback. And, in most cases, the seller will have already left positive feedback for you because you're awesome and were quick to pay and were polite and friendly with any written communication. Most of the time (at least back in the day, i.e. 15-20 years ago), the seller would let you know that a) your item is on the way, and b) positive feedback has been left for you. More often than not they would actually request that you also leave positive feedback for them which I always found tacky and annoying but I did anyway, and would have regardless if they requested it or not.
Now, 15-20 years later, I am selling off said model horse collection (don't have a spare room to display them, wouldn't want to necessarily anyway, and tired of storing them). So now I am a seller and not a buyer, which means that I am obligated to leave positive feedback first if I hope to receive it in return (because once I ship, my part is done, whereas the buyer has to wait to receive the item to know if positive feedback is warranted).
So, in the last few years I have probably sold maybe 8-10 horses on Ebay, have always shipped promptly after receiving payment, have always left a friendly, polite message letting the buyer know the item has shipped, what the tracking # was and thank you for their business, and have always left positive feedback for my buyers (assuming it was deserved, there were a few I didn't leave any feedback for--leaving negative feedback is a last resort if things were REALLY bad), and NOT ONCE have any of the buyers bothered to leave positive feedback for me in return (maybe once, can't remember for sure) . It's so frustrating and really kind of rude. I would have never done that as a buyer!
Then last Saturday the 21st I sold another horse. By Tuesday I still hadn't received payment. I sent a polite message saying that I'm ready to ship as soon as I receive payment, let me know, blah, blah, blah. I got a message back saying thanks for my patience, they will pay on Friday the 27th, hope that's ok. I responded with sure, that's fine, thanks for letting me know. Then yesterday, Friday the 27th, I get another message saying, sorry for the inconvenience but they will pay me on Monday. Eye roll. We'll see what they say when Monday rolls around, but if they don't pay I'm going to go ahead and report it and possibly leave negative feedback. And by the way, they have 100% positive feedback and a bunch of comments about their fast payment, etc. So apparently, out of almost 200 transactions, I am the only one they have decided to pull this on? Whatever.