Earlier quoted context omitted.
Amazon does a pretty good job automating returns. It’s also good enough to be a differentiator when choosing where to buy.
I had an Amazon item that didn't show up / got lost by UPS. The process presented by Amazon for this was pretty silly / tedious: 1) Initially, the tracking page said the item is late, maybe lost, if it doesn't arrive by X date (2-3 days after it was due), check back here to initiate a replacement / refund. 2) I went back on X date to arrange a refund. You click the button, initially it takes you to an automated chat…
Pretty easy in my experience--I expect this process with any other vendor would be much more time-consuming--but as you say it may vary depending on whatever arbitrary factors.