“We wanted to bring two very different films with extraordinary stories to the screen”, says Kevin Feige. “For this reason we also removed Part 1 and Part 2 from the film titles that we had originally announced. We wanted to offer the audience a self-contained experience with each film. Some might argue that ‘Infinity War’ ends with a cliffhanger. After all, these characters mean a lot to all of us, and we know that the next film will be released in a year’s time. Of course we understood that, but that’s not how we regarded and saw this project. For us it was a story that came to an end with the victory of Thanos. That’s why the film doesn't end with pictures of the beaten Avengers and Cap’s statement: ‘Oh God!’. Instead, the last image shows a satisfied Thanos, who went through hell but reached his goal. So it is Thanos’ story that is told here in its entirety”.
Interview 25. April 2019
Marvel Boss: “Thanos’ Story Is Told Here in its Entirety”
Producer Kevin Feige decided very early on that he didn’t want a long film that was simply cut in half. That's why “Avengers’ Endgame” isn’t just called “Infinity War, Part 2”.