There are many reasons why Thanos was able to succeed in Avengers: Infinity War. More than 14,000,604 reasons, in fact, according to Doctor Strange. The Avengers were always going to lose and it was because none of them had the help they needed when the Mad Titan confronted them with the power of the Infinity Stones. They are certain to learn from their mistakes in the upcoming Avengers: Endgame, thanks to one crucial change.
The Russo brothers revealed as much when they sat down with Rotten Tomatoes and explained why -- in their view -- the Avengers lost. It wasn't because of anything that actually occurred in Infinity War. Their defeat was guaranteed way back in Captain America: Civil War.
"Civil War was where it started to come into our brains because, as we were executing that movie, you know, we wanted to break up the Avengers and shatter that relationship -- at the heart of it -- between Steve Rogers and Tony Stark [...] two of them to have a falling out and have an irreconcilable problem was really devastating to the team as a whole," Anthony Russo explained. "That's when I think our brains started to open to 'oh my god, they're so vulnerable now. Now, what happens when Thanos comes?'"
In the upcoming Avengers: Endgame, it appears that the original Avengers are together again and preparing themselves for a second battle with Thanos, the powerful being who wiped out half of all living things in the universe. The reassembled team was shown in recent trailers which teased the long-awaited reunion between Captain America and Tony Stark, who spent Avengers: Infinity War far away from one another on different sides of the galaxy.
How the Avengers reconcile is a mystery at this point -- as is the case with almost all of the major plot points of Avengers: Endgame -- and the Russo brothers have put a great deal of effort into maintaining that secret, leaving eager fans with questions about how the original team will undo the Decimation and how Thanos will fare against the full force of the Avengers.
Directed by Anthony and Joe Russo, Avengers: Endgame stars Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Don Cheadle, Paul Rudd, Brie Larson, Karen Gillan, Danai Gurira, Benedict Wong, Jon Favreau and Bradley Cooper, with Gwyneth Paltrow and Josh Brolin. The film arrives April 26.