Dumest thing I never knew

The single most dumbest thing I never knew until recently last year was how to reset a single start button computer. I wondered and wondered how can manufactures could remove the reset button for a world full of windows and no doors what if there is a fire(read "hang") how do I get out if the windows are closed ? I wondered the day I was shown how I almost knocked myself unconscious because its so dumb. Long press the power button and you are able to hard reset a computer (read "laptop")
 And no one made that obvious to any one except the genius who created that and the other genius who removed the start button in win 8 .God they must be well paid to come up with such unuser friendly user interfaces.