10 Characters Who Proved Captain America WRONG
3. Himself
Everyone goes through life, proving themselves wrong at one time or another. Telling yourself you can't do something but pulling it off is certainly one way, but for Captain America, it was more about a bad decision he made in the MCU that ultimately came back to bite "America's Ass" in the end.
In Captain America: The Winter Soldier, Cap learns that Tony Stark's parents were killed by HYDRA; more specifically, they were killed by the Winter Soldier, aka, Bucky Barnes. When he learns this key piece of information his friend and ally would certainly like to know, he keeps it to himself.
The following film, Captain America: Civil War, sees his decision to withhold the information about Tony's parents ends up blowing up in his face. Tony does not take the news well, and he sees Cap's silence on the issue as a betrayal.
What follows is the worst fight in the MCU, in that it divided the Avengers, and drove a wedge between Captain America and Iron Man, which wouldn't be resolved until half the universe gets wiped from existence by Thanos. Cap was abjectly wrong in his decision not to tell Tony about his folks, thus proving himself wrong in the process.