I order something on Prime, then it doesn't show up when I expect it to, I get no notification of any delays, and then when I log in to see what's going on they have changed the original expected date so I can't even see what I was originally promised unless I took a screen shot.
This has been the case on 2 thirds of my deliveries over the past 3 months. And I'm not even going into the sham that is 3rd party selling.