People want to see patterns in the world. It is how we evolved. We descended from those primates who were best at spotting the telltale pattern of a predator in the forest, or of food in the savannah. So important is this skill that we apply it everywhere, warranted or not.
Benoît Mandelbrot, in 'The (Mis)Behavior of Markets (2004) co-written wiith Richard L. Hudson, Ch. 12, p. 245