Avengers: Endgame directors explain why Superman is "difficult" to get right
The Russos talk about adapting the Man of Steel for film
In an interview with Business Insider, Joe Russo said that the Man of Steel was "a very difficult character", adding: "You have to find an emotional flaw or weakness in the character in order to make them vulnerable."
Anthony expanded on this point, stating: "The more powerful a character is, the more difficult [it is] to deal with that character on a narrative level.
"As storytellers, and the way we explore characters, we always look for vulnerabilities in characters because that's where characters become interesting. They're superficially interesting in their strength, but they get much more depth when you find where they don't have that kind of strength.
"In general, the more powerful a character is, the more tricky that is."