For the question in the begining of the video, the first idea I came up is the flow of energy. Something like water, which you can generate electricity from it if it's high engough. You have to get rid of the water, but you extract the potential from it. The energy might be same, you have to get rid of the energy, but you extract something from it to use.

Later in the video, I learn that kind of things are called entropy.

Phsysic is fun, as long as there is no exam.
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The Most Misunderstood Concept in Physics
by Veritasium
https://www.youtube.com/watch?v=DxL2HoqLbyA