Unless it is a game that I'm not sure if I want to play or not, I almost never wait for sales. When a new game comes out in a series I love, I want to play it right away after release! The only exception on this would be for Steam games. Steam sales have been good to me, and if I'd been able to afford games during the last sale I would have been able to save more than $60 on my wishlist items. Definitely worth waiting on a discount there, unless, again, it is one that I've been really wanting to play or a new release in a series I follow.
When Persona 5 comes out, for example - there ain't no way I'm waiting for that, that game is mine. But on a game like, say... the new Animal Crossing. I would like to get the game, but not one I'm hyped up about, so I wouldn't mind waiting for a sale of some sort.