It's because the layperson isn't constantly observing systems and thinking about how effective or efficient they are. Their minds just don't seem to work like that. (Perhaps there's some area of expertise they have which applies outside the realm of technology...)
While fumbling with some poorly designed UI, they don't appear to get as angry and exclaim, "This user interface sucks! My previous car had a button to turn the A/C on and off."
They just accept it. I could get philosophical (thanks for asking!), and I think that's a general problem with humanity. Too many are too accepting of just whatever comes along, and that's how we converge on terrible designs and terrible public policies and on and on.