Everything strives to an average, a normal measurement.

Entropy is the theory that energy becomes more chaotic or random over time. It is the opposite of normalisation, which is a pull on a system towards the average.

We measure a sound wave around the average measurement that we call Zero. The same with a beam of light. Zero is an arbitrary point, there is no such thing as Zero, it is a philisophical concept.

The sunglasses effect.
When you wear a pair of sunglasses eventually you cease to notice them. Your body has normalised the information around whatever its in.

The Salt Effect
When you eat a lot of salt and flavourants other food becomes dull by comparison. You complain that food has become tasteless, but it is your tongue that has normalised. Stop eating lots of salts and flavours and normal food regains its flavour.

When you are exposed to violence a lot it becomes normal.

When you are exposed to good things a lot it becomes normal.