The why game. A thing that young children will often do purely to annoy their parents. Yes, it's annoying, and tedious. Children use it all the time. And adults should use it more often.
The why game can be useful for loads of things. It can be used for any question. For instance, why do Brits pronouce the letter "Z" zed and Americans pronounce it Zee? Well, states started using their own version of the letter. Izzard, zend, etc. Eventually, someone came up with "Zee". This swept over the nation, and everyone started pronouncing Z that way.
You could ask, "Well, why did Brits call it Zed in the first place?" It originates from the Greek letter Zeta. You could keep asking, "Why?" The why game is infinite, which means there is an infinite amount of information that can be gained from it.
Now let's think about how useful this was. Not only do you get a lot of information, you understand how it is connected. That is the most important thing. Imagine if schools taught us this way! Schools normally teach us by just shoving information at us. With the why game, we can see how it all ties together.
Adults should use it as well. Imagine that you're studying quantum mechanics. Give yourself a question that you know the answer to. Then play the why game with yourself. You will get so much vital information!
Overall, the why game can be a pretty useful tool. I encourage you to use it as much as possible.