The Lensman wrote:
Why? Joss Whedon was at the helm of a train that was already heading down hill, full speed, when he sat in the engineers chair. The MCU had been working towards Avengers for years, there was already massive anticipation for the film and and no one was doubting that it was going to be a huge hit. The only surprise was how huge it actually was.
Please, there might have been a lot of anticipation for Avengers, but it still could have VERY easily ended up either a completely trainwreck, or just another average, by the numbers superhero flick, given all the different characters involved.
Whedon might have made it look deceptively easy, but he still had to juggle a LOT of different story elements to make the thing work. He not only did that brilliantly, but in the end made an even better
movie than most of the ones that led up to it, which is no small feat.