McDonald's is my favorite place to take a dump while on the road so I stopped by one a couple months with a self service machine. Spent maybe 30 seconds futzing around with it, couldn't figure out how to order a coffee proceeded to order one in about 10 seconds at the cashier. Self serve is not that hard but big companies like that suck at making user interfaces. Just think of how slow the stupid checkout machines are and they are 3rd or 4th gen these days
This is weird, because I have a sort of similar reaction, but at a much lower intensity. The self-serve McDonalds machines were slow, but comprehensible to me. Likewise, self-checkout is occasionally frustrating, but generally much faster than waiting for a human cashier in my experience.
It's more that I couldn't be bothered to figure it out since the cashier is faster. It's the same thing at the grocery store. If I have simple items and the line is more than 3 ppl long I go self checkout but often there is a line for that and it moves at roughly the same speed (even though there are 4 stands). The bigger problem is bulk items, fruits, vegetables and alcohol, those take a lot of time to enter into the system. Way too many menus and buttons and very high error rates.