The Canadian Broadcasting Corporation reports on a former math teacher who claims to solved the question "Which checkout line up will be fastest?"
In a nutshell he has concluded that the number of people in the lineup is more important than the number of items a person has in their cart.
The critical factor, he says, is the average of 41 seconds that it takes a shopper to pay the cashier and engage in idle chit chat.
So a long line of people in the Express line, with two or three items each, will actual move slower than the checkout with one guy with a full shopping cart.
YMMV.
(Score: 2) by Grishnakh on Monday September 19 2016, @09:06PM
The single line optimizes all those things at once. It's mathematically superior in every single way.
The only thing it's bad for is (as another poster pointed out) it likely reduces the number of impulse buys from the crap for sale in the checkout line (the place where they have gum, gift cards, drinks, Weekly World News, etc.), because customers are moving through it faster on average.
But for customers, a single line is always better: it's always first-come-first-served (you don't have to try to guess which line will be fastest, there's only one choice), your wait time will be minimized (there's no chance you'll be stuck behind some slow-ass who's paying with a check: you'll just go to the next available cashier), and it maximizes throughput (no cashiers will stand empty because customers didn't see them).
I guess there is one exception: if you're prescient like Paul Atreides, or some kind of mind-reader, or can otherwise somehow predict which line will be fastest for you, then you'll do better in a traditional checkout arrangement, but you'll do so at the expense of other customers.
(Score: 2) by isostatic on Monday September 19 2016, @10:14PM
No it doesn't solve the problem, as there is a non zero time from head of queue to counter.
And impulse buys have nothing to do with it - many supermarkets have impulse buys in the single line and at the till while the basket is wrung up.