Microwave ovens, an unnecessarily bad design
Does it take more time to set up the machine than to warm your food?
Even if the controls are labeled in a foreign language, I should be able to cook my food.
from Flickr by Jeremy Hall under CC BY 2.0, croppedThe only thing that I need to set is the time that my food should cook. I do not need more controls.
Any extra button will make it harder to figure out, which controls to use to set the time. Or worse, they require many taps to input a number. Maybe with time I can remember the right buttons, but why not make it simple?
How to fix it
Have a turning knob like a cooking timer.
You can add a second turning knob for setting the power, but it should by styled in a way that the timer knob is the only important control.
Almost perfect. If the knob for controlling the wattage would be smaller and less colorful, it would be basically impossible to use miss the correct control.
from Flickr by 1Day Review under CC BY 2.0, cropped