One of the great joys of the Marvel Universe is following the Avengers' constantly changing roster. Ever since the team was overhauled entirely in 1963s The Avengers Vol 1 #16 (by Stan Lee, Jack Kirby, Dick Ayers, Stan Goldberg, and Artie Simek), Earth's Mightiest Heroes have remained mercurial, with numerous heroes coming and going over the decades. However, the "Big Three" of Captain America, Iron Man, and Thor have nearly always been present, often providing consistency during team transitions. Nonetheless, all of this changed with the emergence of the New Avengers in 2005. Although Iron Man and Captain America (as Nomad) graced the team's original roster, the New Avengers carved a path for themselves without needing Marvel's trinity.
Source：https://www.cbr.com/new-avengers-didnt-need-marvels-trinity/
