There were a lot of twists and turns in Avengers: Endgame, which left viewers with a plethora of questions. Where did Loki go with the Tesseract? What timeline did Steve Rogers live in when he stayed back with Peggy Carter? How did Nebula transport Thanos to Earth without any extra Pym Particles? While most of those questions are left to the viewer's interpretations, there's one that begs an explanation. How did old Steve Rogers know to show up on that bench at that specific time in the future?
Marvel Studios head Kevin Feige spoke with Empire to promote the recent home release of Endgame, and when asked that very question, he avoided it like the plague.
"That's a good question, for another time... Who says that? Maz Kanata in The Force Awakens in regard to, how did Luke Skywalker's lightsaber get in your castle. Ever since I heard that line I said, I'm gonna use that – a lot!"Of course, Feige is referring to the bizarre appearance of Luke Skywalker's lightsaber in Maz's castle after it was lost during his fight with Darth Vader on Cloud City. There was absolutely no reason why his lightsaber should have been with Maz, and no explanation was ever revealed for how it got there. It looks like that's going to be the case for old Cap and that bench. After Steve Rogers traveled back in time to return the Infinity Stones to their respective dates and locations, he somehow showed up as an old man right by his departure zone next to Sam Wilson, Bucky Barnes, and Professor Hulk. Sam eventually speaks with old Cap and receives the shield from the man himself, but fans are still wanting some answers.
Perhaps an even bigger question than how Cap got there, is: Will there ever be an explanation? Probably not Marvel fans. Chris Evans has (for now) retired from playing Captain America and his story with Peggy Carter will likely not be explored in any upcoming projects. The next two years of MCU projects have been revealed and none are set to feature Peggy or Steve, meaning their story closed with their dance at the end of Endgame.
Many fans have their own theories posted on Reddit, but most revolve around the timeline in which Steve Rogers lives with Peggy in the past, and not how he showed up perfectly on time at the bench with his buddies. Interpret it how you will Cap fans because Feige definitely isn't going to let us know anytime soon.