Hidden interface controls that affect usability

    The other day I was locked out of my car
    the key fob button wouldn't work

    Why didn't I just use my key to get in? 
    First, you need to know there is a hidden key inside the fob.
    Second, because there doesn't appear to be a keyhole on the car door,
    you also have to know that you need to disassemble a portion 
    of the car door handle to expose the keyhole.

Hiding critical car controls is hostile engineering. In this, it doesn't stand out much in the modern car experience.

All of which you should know, and can be easily found with a quick google. The moment we got a car with no physical key my first question was “what’s the backup option and how does it work”.

Basic knowledge about the things you own isn’t hard. My god there is a lot of old man shakes fist at cloud in here.

Knowing how to get around a stupid design doesn't make it any less stupid.