If the machines suck, there definitely are "others" who should be blamed for that - both those who created the machines, and those who decided to install them.

True, absolutely

It's not just throwing machines out there without proper UX studies and adapted to each case

The worst offenders in that regard are probably public transit ticketing machines. In addition to every system being different, in some locations, you now have lines of possibly jet-lagged tourists who may not be native speakers of the default language fumbling with machines and nbot quite sure what to do with whatever pieces of paper the machine spits out.

There are definitely machines that suck and treat any little sensitivity as a potential theft. Blame goes to the machine makers and the decisions makers of the store. Generally self checkout definitely has its 'lane' with the 'less then 10' items shopping trip.