Then the next day I couldn't figure out how to start the rental car again, because instead of a key it had a button, and even though I kept pushing it the engine wouldn't start, and this odd little lumpy icon would light up on the … what I was supposed to do when I started the car, which of course I would have done automatically if I'd just had a key and not this weird button completely confounding my intuitive knowledge of how to start a freaking car. … …

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Usable Help – Changes disrupt knowledge