People think in terms of cause-and-effect. We're programmed by nature to see patterns, sometimes even when there are none to be had. Our brains have a hard time accepting randomness or chaos.
We blame the victim because it resolves the uncertainty of randomness in our head. It's not that something bad happened to you because of bad fortune, but because you did something to bring it on yourself. It assigns a cause to the effect we witnessed.
It's a stupid and frustrating part of human psychology that most people never have the awareness to challenge
