Amazon directly competes with 3rd-party sellers. I used to sell various products on Amazon about 10 years ago and as soon as I started seeing a decent amount o

Amazon directly competes with 3rd-party sellers. I used to sell various products on Amazon about 10 years ago and as soon as I started seeing a decent amount of sales, A listing would appear by Amazon (not a 3rd-party seller) and undercut me. My sales would soon disappear after that. They clearly use your sales data to make money and directly compete with you. This combined with their atrocious support for sellers has turned me off to their marketplace completely. Ebay, on the other hand, doesn't do this and I think this is why Amazon is able to make so much more money.