Nature is full of imperfection and chaos. To the human mind seeking perfection and order, this is highly unacceptable. We seek symmetry and linearity, both of which do not exist in the natural world.
A Zen lore: There were two Zen learning centres having a common wall. One was old and the other new. The new centre had beautiful gardens with many people looking after their upkeep. One day, before an important function, the gardener was busy cleaning all the dead leaves that had collected on the ground below a slender tree. The old school master was sitting on the wall observing this. The gardener cleaned all the leaves, stood back watching his work with pride and said “perfect”! The old school Zen master said, “no, it is not yet perfect” and walked up to the tree and shook the trunk. Many leaves fell and collected on the ground. The master said, “now, it is perfect”.