After playing Tony Stark for over a decade, Robert Downey Jr. knew that the ride needed to come to an end. 

Following the events that took place in Avengers: Endgame and the reconciliation with its aftermath in Spider-Man: Far From Home, the Marvel Cinematic Universe was about to venture into the great unknown with the introduction of new characters and worlds in Phase 4. Downey Jr. believed that the best approach to tackling this new terrain would mean that Iron Man and Captain America could no longer be prominently featured in these upcoming projects. 

"We had to get off. We opted to, and knew it was part of the job to get off the bus while it rolled on to other destinations," Downey Jr. said in the fall issue of Disney twenty-three magazine, according to Digital Spy. "There's something very sobering about it. I'm glad he and I will be there to welcome others as they retire their jerseys."

Despite the outpouring "I Love You 3000" messages that arose following Endgame's theatrical release, Downey Jr. says he's "loathe" to talk about leaving his mark on this world when his MCU co-stars, Evans and Mark Ruffalo, have been doing just as good, if not better, job than he has.  

"I really don't need to look any farther than my co-stars. Mark Ruffalo is an activist, Chris Evans is a diehard American and proponent of true democracy," Downey said. "I don't really have the gumption, the skill set, the drive, or the humility either of those guys do."