symmetry

We love patterns. We are really good at spotting them everywhere, even if there are no inherited order in all those things. We also consider symmetric things beautiful. 

From computational viewpoint that makes a lot of sense. Symmetry and patterns are more efficient to generate, process and store than less ordered data.  Maybe that's the reason our brains do find such things satisfying.

This love of order can also function as motivation sometimes. Working towards making something to follow a pattern can be satisfying. No matter what it would take to achieve it.