Perhaps there has been some convergence towards microwave usability that I haven't experienced yet.

Microwave oven keypad controls are a terrible example: I've had some terrible troubles attempting to use ones that force you to set power level - half the time start isn't even obvious...

I bought one with a timer knob and a power knob that is mostly usable (but still poorly designed in some ways). Usable enough that I bought the same model for my parents. I would like the power level to be a slider not a digital knob, even though the knob is an improvement over a keypad.