Self-checkout. I got to the store, get my groceries, and see long lines of people standing waiting to checkout. There is only one clerk checking people out; everyone else has to go wait in the self-checkout line. We all stand and wait. One person has a problem finding a code for veggies. Another can't get their card to work. Another is wondering why their is a price discrepancy. And so on; each with a problem that could easily be solved by a clerk in no time at all, but now they have to stare at the machine, wait for the machine to tell them there is a problem try to figure it out themselves, they go to the clerk at the computer screen who can now come and take a look. That clerk, by the way, does not particularly enjoy dealing with customers and it shows, because they are all coming to her with stupid questions. Clerks in general now don't like interacting with customers because they see customers are looking at them as a kind-of self-checkout+.
When I get to the self-checkout, finally, I feel ten people waiting behind me. I can't make a mistake! I have to hurry! I scan items quickly, I see them rolling down to the end of the conveyor belt, piling up. No mistakes! Then I have to run down and pack all of my groceries before the next person begins, but it's too late, they are sending down their peanut butter, milk, etc.