system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do magnets "die" after a while of being used?
gpt
Imagine the atoms in a magnet as little arrows. When manufacturing magnets, all of the arrows are arranged In one direction. This is done because it makes the arrows useful.

⬅️⬅️

⬅️⬅️


These arrows don't like to all go in the same, linear direction. This is because they don't like their tips touching, or even getting near each other. As you can see, when they are all going in one direction, the arrow tips are very close the ones above. The arrows don't like this, and only want to be near the end of another arrow. This makes the arrows unhappy, so they become unstable and want to move.

 When the arrows are in a position they enjoy, they become happy. When they are happy they are stable and don't want to move.

↙️ ↖️

↘️↗️

Because the arrows are so closely packed it is hard for them to rearrange in a way that makes them happy. 
One thing that makes this easier is when they are hot. This gives the arrows the energy and wiggle room they need to point at something they like.