I use self checkouts regularly in both the US and Switzerland. The contrast in UI design is staggering. The US self checkout machines (e.g. at Safeway) are enormous, employ voices constantly hectoring me about bags, items placed in the wrong location etc, and do everything to disrupt my rhythm: https://c1.staticflickr.com/9/8382/8539442967_7917df5cde_b.j...
Swiss self checkout machines are small, silent except for beeps, and fast: https://subito.migros.ch/dam/jcr:afca29de-d490-4621-8844-868...
The latest option is that you can grab a scanner before shopping, scan items as you place them in your cart, and just walk up to a station to pay.