10 MCU Theories That Come Directly From The Creators

5. The Hulk Wasn't Scared Of Thanos, He Was Tired Of Helping Bruce - Avengers: Infinity War

With Bruce Banner (Mark Ruffalo) suffering through, er, "performance issues" in Avengers: Infinity War, many fans took The Hulk's absence as proof that the Big Green Dude was scared of Thanos after their one-sided fight at the start of the movie, and therefore refused to face him again.

But on the director's commentary for Infinity War, Joe Russo - who didn't write the movie, remember - offers up his own thoughts on The Hulk's refusal:

"What makes him unique as a character is that there is a host body that is being fought over by two distinct personalities who hate each other. And both want control of the host body. So we thought an interesting direction to take him in is what if Banner, who typically uses the Hulk to solve crisis situations, what if the Hulk were no longer interested in solving those problems for Banner? So that the relationship is becoming increasingly dysfunctional. That's what's going on here...People have speculated whether there was some fear on the Hulk's part about having to face Thanos again. But I think ultimately what it is, is that he's tired of playing hero to Bruce Banner."

The theory of course dovetails quite neatly into Endgame's fusion of Banner and Hulk, where after eighteen months in a gamma lab, he's able to "put the brains and the brawn together."