Modern Warfare 3, Final Fantasy 13, and the Thief remake all taught me to never buy a game at release and that you can't trust IP. I'll always wait at least a month until the dust has settled and sometimes will just wait for a discount.
Practising delaying gratification is great for the mental health and ensures you're making an informed decision not getting swept up in the hype. I'm sure I've played much worse games but never after waiting with such baited breath and paying so much for them.