I still haven’t used these before, but I imagine I could figure it out just fine. I just saw some new ones when I was out grocery shopping. There were four but only two were active. One woman was having trouble so there was a guy there helping her (probably also there to make sure people don’t steal stuff). I had heard from my sister about a similar situation in the Boston MTA. Basically they installed subway card machines, but the user interface of the machines was so poorly designed they had to get someone to stand by the machines and explain it if people were having trouble. Clearly the most efficient way to do things is to eliminate one human job and replace it with another that’s perhaps more annoying to do than the original one.