I used to work at a grocery store and the checkers and baggers would work hard to be fast. The checker would be scanning stuff as fast as possible and I'd be trying to keep up with the checker. By the time the customer paid all his stuff would be ready to go.
Usually there would be less baggers than cashiers so I'd be going from counter to counter to keep the lines going.
The cashiers got a scan per minute count at the end of the day and the manager would let us know if we were slowing down. 30 scans per minute was considered good. That was with signed checks most of the time which was the slowest part.
Fast forward to today, cashiers are slow as fuck and there are no baggers. A line with 3 carts takes forever. I am faster at the self checkouts.