Among various commentaries I've read over the years, one of the most repeated is that stocks have individual tendencies that are above and beyond market noise or fundamental outcomes. Meaning that XYZ stock will almost always do this or that whenever an incident occurs while ABC stock may do the opposite or something in between. Is this just anthropomorphizing or personalizing the stock to the individual trader or is it a real phenomenon? An offshoot of this is to especialize certain price levels around whole numbers (10/100/1000/10000). Whereas if said stock or indice breaks or falls below that marker certain things will happen to it, even though intrinsically their is nothing remarkable between 99.99 and 100.00 other than a 1c price difference. As a result, traders may be making leaps of faith which in all practicality mean nothing in reality over time.
...best proof of this is in Katz and McCormick, where they demonstrate exhaustively that no system works for every future, but for every future there is a system which works!