The Importance of Probability in Games

I've mentioned before on the game or asked why aren't more triple A games doing sort of a bergal act structure or more randomness? And I can also see that being element where like, you don't want things to show up that look messy. That really rubs up against like a really pristine presentation or even things like X-com that look awesome 95% of the time until it looks terrible and not wanting to change your experience with that.