The rules are much tighter now, and there’s much more you need to know to avoid the pitfalls.
In the mid-2000s I worked for an online bookseller. His instructions were to list against the most popular product page for the book we had, regardless of whether or not it matched, and use the condition notes to indicate when we were selling an outdated edition, or even a completely different book by the same author. Needless to say, we got a lot complaints from angry customers who thought they were buying the book that Amazon was selling, and not the 1927 version of the textbook they needed for class. My job was to accept the return with a restocking fee, while lecturing the customer about the importance of reading condition notes.
He was too cheap to pay for delivery confirmation, which turned out to convenient, as his shelving system was so disorganized that we routinely failed to locate at least 25% of our orders. Our process was to confirm shipment, then take turns looking for missing books. When the customer would start to complain, my job was to repeatedly assure them that their book had shipped and was merely slow in the mail. If we couldn’t find the book before the customer finally lost patience (typically, one month), we’d begrudgingly issue a refund, claiming that the book had been lost in transit.
If a book actually was lost in the mail, however, my instructions were to tell the customer “tough luck,” and complain that Amazon didn’t give them an option to buy insurance, like on eBay. I hated that my job was to lie and cheat, and ultimately left for this reason.
The metrics system was implemented to prevent these kind of shenanigans, which is good, but of course it creates a lot of stress if you’re a low volume seller vulnerable to a run of bad luck. And this, of course, was before intellectual property was being policed as zealously as it is today, so you also have that to run afoul of.
The money, of course, was better because you were buying from (and competing against) people who didn’t use computers and were slow to understand that you could sell things on the Internet. Today, of course, it’s hard to find an auction where everyone hasn’t looked up everything online prior to bidding.