Part of this is that Costco, unlike most retail outlets, treats their employees well and tries really hard to keep them around. For example, notice that the Cos

Part of this is that Costco, unlike most retail outlets, treats their employees well and tries really hard to keep them around. For example, notice that the Costco nametags always have an "Employee since" on them, and in most of the stores I've been in you will even see some with the 1990's on their tags, and lots of people with 10+ years at Costco. They aren't doing the standard retail employee churn- typical retail stores have 100% turnover per year. So Costco is willing to accept a slower-ramp up period in exchange for longer term speed and efficiency, whereas companies which churn their employees care far more about initial discoverability and getting someone to be moderately capable very quickly. My wife, a decade ago, worked at the transition of her pharmacy from when it was a local retail chain and then was purchased by one of the national chains. The local retail chain, which was a reasonably pleasant place to work for its employees, had a computer system that was an ancient DOS app like Costco uses, and when my wife would get a call from another employee on how to do something unusual in the system it was lots of "now hit tab three times, then Alt-F10 and select the glorbaldall from the drop-down and then two more tabs and then ctrl-shift-S and enter the frazzlematazz" and the new company was hellish towards their employees and had a slick new web interface with lots of menu options so you could eventually find what you needed without the keyboards, but you could never get to be as fast as my wife was on the older system.