Maybe it’s here already, but I want to mention the “self check out Na**”, (** just in case the real word is politically incorrect.)
“She” reminds me of the rules in that Seinfeld “Soup Na**” episode.
Apparently you have to wait until she says put your empty bag down, then put it down, but don’t move it! And don’t add anything until she says, and don’t pick it up until she says you may. Any mistakes, she announces it, and you are supposed to wait for help, while everyone looks at you like you are annoying.
I try to avoid it, but used it today, and one of the helpers told me the secret was to put the bag and a weigh-able item on the scale at exactly the same time.