When being attacked, Rockhold moves back and switches to what looks like a karate stance. His entire right side is facing the opponent, he has to turn his head to look at the opponent. Basically, he cuts down his resources in half: 1 eye, 1 arm, 1 leg. Not only it's alot harder to turn your head to see the punches coming with 1 eye, you have only 1 arm to defend yourself: the front one. Look at the 2nd gif, he defends himself against Romero's left with a right hook. What happens if that hook misses? Romero's left has a huge area to land on: the face, the side of the head, the back of the head. When the head turns sideways like that, it cannot do any bobbing and weaving, it's a sitting duck. Rockhold's left hand is also useless while Romero can still follow up with his right hand any where to the exposed face and head. Basically you face the opponent sideways while he faces you head on. Bad habit.