You'd think it's hard to screw up a rotating knob, but they've found ways to do that as well! When I went shopping for a stove years ago I found out that some have knobs that only go one way, so to switch a burner to max, you have to twist it all the way around. Extremely annoying.
I ended up going to a showroom and twisting all the knobs of all the stoves to find out which ones didn't have that limitation. I must have looked like a crazy person, but I got one I liked in the end.
The stove I ended up buying had one variable-size burner, and that knob had a bounce-back switch at the end, so you have to turn that knob the wrong way around to max it, but I could live with that. Why a regular burner would have the limit beats me. The only thing I could think of would be some sort of extremely crude and ineffective child-protection, but all stoves have a child-lock anyway, so what's the use?
The stove where I live right now has knobs whose full range of motion is a quarter-turn, and the flame goes out if you turn it more than halfway down, so effectively you only have one-eighth of the knob to use. If you try to set it to low heat, you'll usually go too far and put the flame out unless you pick up the pan and watch the burner while turning the knob a millimeter at a time.
It's absolutely amazing what people can manage to screw up.
One integration test should be to take the engineer in charge, bind one arm behind his back and tell him to make Spaghetti aglio olio peperoncini for Gordon Ramsey waiting with a Santoku knife ready for some action.
Edit: To clarify - Aglio olio is what they cook in prison in Good Fellas. It's both the most simplest pasta dish and the easiest to screw up - overcook the garlic a bit and you get garlic chips instead of melting their flavour into the sauce.
Used an 80s microwave for the first time in years, a few months back. I'd forgotten how nice they are.
Power knob (the kind that clicks to exact positions), timer knob. Only interface. Set power (or don't if it's already where you want it), turn timer to where you want it. Done. Pull door to open, not even a button for that. 100x better than the interface on modern microwaves.
