Image via WikipediaI had just joined the line at my Tesco (supermarket chain in the UK on the cheaper end) for the self-service check-out, cursing that I would subject myself to those horrible machines yet again. The alternative was joining the staffed queues, each with a customer or 3 already waiting, shopping carts filled with enough food for an army regiment. I heard a voice calling from the 10-items-or-less line. That line is usually closed in the evenings, so I was surprised to see it was staffed right now.
-- "I am surprised, this line is usually closed."
"Yes, I am trying something new to make things better."
-- "If you really want to do that, fix your self-checkout machines."
They are a case study in how usability is more than logically placed buttons and clear pictures and even a friendly voice. Usability is not just going to be fixed with a nice sauce of wireframes and good visual designers if the underlying system does not support how humans act.
Humans want to get things done quickly in a supermarket. They want to scan quickly, put the item away, and go to the next. They don't want to have to wait for a slow scale that needs to have the item placed on the belt just right 5 times before it registers, they don't want to wait to go to the next step of paying and getting a bill until the voice loop has slowly and painfully spoken about what button you should touch and how it will give you clubcard points when the human already knows from previous times, they don't want to wait 5 seconds between pressing a touch screen button and the screen reacting for god knows what reason in an age their game computer at home will penalize them for clicking a millisecond too slow. I defy anyone to use these particular machines at that location more than three times without wanting to punch their screens out in a fit of hot rage. No amount of perfectly chosen colors will compensate for the aggravation of having to use a machine that expects to impose its own order and speed of doing things.
Especially when it is unnecessary. The self check-outs I used in the US were all fast, scanning and itemizing quickly, not needing to finish their display animations and prompts for one item when the user was already scanning the next or inserting coins, simply paying attention to its input and processing each as fast as it could. As a result, they never got as confused as the machines in my Tesco do, they never needed as much human attention and help, and one supervisor could indeed check all four of them without being overwhelmed. Actually, this goes for the self check-outs I saw at Boots (a UK drug store chain), which are obviously from the same manufacturer as the one in Tesco, yet did not get in the way of the actual checking out.
"Yeah, we know about the machines. But we finally convinced the manager who is responsible for ordering them to stand at the supervising station for a full day. He will be ordering new ones."
That is the second lesson: nothing's gonna change about a painful system until the people with actual power experience the pain. Customers complaining, systems being down, staff overwhelmed -- doesn't matter; if customers can't use them they will just get in line for the manned check-out counters. Once they are inside the store and have full baskets they are captive anyway. But make the guy holding the purse actually feel what he is doing to his staff with that terrible equipment, and suddenly all kinds of upgrades are possible.