The only truly intuitive interface is the nipple.
— Jay Vollmer
I’ve always kind of liked this quote. But recently, I realized, it’s all wrong. Not only do many babies need to learn to breast feed, but the human nipple is terribly unpredictable.
If a baby suckles on a male nipple, nothing happens! Suck on a female nipple, and only then do you get results. A baby could become totally discouraged from the first attempt and stop suckling on nipples. It would arguably be insane to do anything else.
The hallmark of a bad interface is doing unpredictable things when pressing the same button. So shame on you, evolution.