I used to sell on amazon, i sold over 1000 items but only ever got about 50 feedbacks. a few people left me neg feedback because of things outside of my control like the royal mail. i got a warning email from amazon saying that my feedback was not to good and i would need to improve, 5 people out of 1000 left bad fb but only 50 left good so my percentage was crap, i email amazon back telling them my concern and even advised them how to better their feedback and how to encourage shoppers to leave feedback, my efforts were in vain and a few week later my account was closed and my funds of £1500+ change were to be held for 90 days, ontop of this some unhappy customer done a a-z claim on me even after i had sent a replacement, so i lost out on 3 units and no money. so i thought i would tell everyone that if you buy something from amazon marketplace you can simply make a a-z claim and the seller MUST issue a refund. this is not a invite for everyone to go and buy something from amazon and then say it never got there but if your buying from amazon marketplace and the seller has over 1000 sales they wont be using recorded delivery. this is because it is more cost effective to cover the loss of 1 item every now and then, versus paying a extra £1 on every item sent. i hope amazon read this and start to protect their seller in future.
There are people out there who will give you bad feedback regardless of what you do i experienced this on ebay years ago for every 499 or so positives i would get one completely undeserved negative.