Well DC ended up with a longer lead up to JL than Marvel had for the avengers. But on the whole they tried to do it faster. IIRC justice league and Batman v Superman Grizley Bear Dance Off both ended up delayed a couple times.
DC effectively just attempted to jump right in on the shared universe thing. They had one movie out. Man of Steel and they went right from that to team ups and introducing as many heroes as possible.
Marvel sort of took their time. For one thing g they apparently planned for years before they actually started on the concept. Put together central story and producing groups. Incredible hulk was apparently the actual first MCU movie, though it bombed and casting changed so it’s no longer included. The early phase 1 movies were entirely stand alone films.
Only tied together by a few characters, chiefly Coulson. And some end credit tags. Fury was a Captain America character who cameoed/debuted in an Iron Man end credits scene. Connections built over time. And we only saw full blown shared universe for the first time with Avengers itself. A lot of the early ties only became clear looking back.
And they adapted as they went based on what worked. Earnest retro Captain America was less popular than Iron Man. So Winter Soldier became a spy thriller. Loki was the biggest thing to come out of Thor (or the only thing) so Loki became the keystone Villain of the whole thing, And the lead baddy in Avengers. Incredible Hulk didn’t work. So they recast. And Hulk became a team guy, And back ended. Until they found a way to make it work. Thor was dragging to. Do they teamed the two up in a wildly different approach to the Thor mythos. Black widow was more popular than expected. So she became the 2nd lead in Winter Soldier. And the key tie between an awful lot of the movies in place of Fury after a bit.
It was effectively a decade before we saw all these moving pieces fully tied together and operating as a whole.
DC tied their whole shebang to the first bankable director they could find (after his career started to stagnate). And ran directly into full avengers phase 3 mode. And hasn’t really seemed to have a clear idea of why.
That’s why Justice League is such a massive problem. It’s not just a bomb. Justice League was the point. Everything else they were doing was about getting to Justice League is fast as possible. And the real money would be made on Justice League. Whereas for Marvel. Multiple tentpole trilogies was the point. Avengers was icing on the cake. And going harder, further and more comic booky after avengers was a risk.
