In BB8, even with maneuvering with America's shenanigans, Eric was still a quite dominantly social player in the game that likely would have won, had America not voted Dustin out.
BB14, I firmly believe Dan should have won, although Ian is an okay winner so no major dispute with this
But BB18 was well deserved by Nicole. Upon a rewatch, you can see that she literally had a say in EVERY persons eviction, save for Paulie. (She had a hand in Corey's, considering nommed against each other). She really used her placement as the underrated returnee and ran with it and won as she should have.