Complain or hideous SOP

Sometimes after following all the SOP to get job done, you don't get complain from the customer you are currently serving. But the next 2-10 people waiting in the queue not knowing what you have been doing because they don't care and they have been waiting. The fatest way to do things will cause the current customer to complain but at least the next 2-10 people won't complain you. Like forgetting to bring card, forgetting to bring wallet, forgetting to bring handphone.... Just to solve this one person problem, I might not even get a good review from this person but I will get complains from the people in the long queue. If I didn't, at least only this one person, the rest of the queue even though fast and also no good review, comparing both, the number of people is definitely lesser. Only people with the capability to complain knows how to write a review. Anyway, if there is no way I am not getting complain, at least I tried not to give money away for free by doing hideous procedure with no clear definition of what is what. Anything that goes wrong have to pay. First thing about doing cashier is actually don't be too helpful the wrong way because the wrong people who gets the help will use it against you. Hold you accountable for everything they can find. You want complain or complains or doing extra hideous thing that cause you more troubles and a fine.