Why does it seem that the stores put incompetent cashiers at the 'fast lane'?

i have complained about this as well and it is something that drives me crazy alot. i have found that when i go to walmart as long as i am not getting like fresh veggies and fruit just go to garden center, camping or automotive. you get out alot faster. one thing is walmart can only schedule a certain amount of people it doesnt go off of what the manager thinks it goes off of sales on that day the year before and what the corp thinks. as far as the training they do train them and yes some are slow but you have to also think ok the person that is checking out now or before them etc did they have there money. did they argue over a price, did they bring something up that didnt scan right or wasnt tagged, did they have to take items off , etc etc. you have to think also those people get tired just like everyone else. how long had she ben there without a break? i mean really. also who did not show up for work that day. there are alot of things that go on that we dont really think about. now yes some are just slow but those are usally the ones that never miss a day, never have a cash shortage, and stuff liek that so the company is going to keep them. most of the time to even when it says 10 or 20 or less the people going in that line have more then that.

Probably because they figure most people will buy more than 10-20 items and will need the more competent people at the longer lines where there's a chance of a higher margin of error for ringing a product, whereas the express lane sometimes have people even capable of "doing it themselves" (are you familiar with Harris Teeter...if you are you'll get it, if not, don't worry about it).