3. Production Has Been Troubled From The Start
A Justice League movie has been in development in some capacity for getting close to a decade now, but various issues - usually terrible scripts - have prevented it from actually going anywhere. Rubbing salt in the wound was the 2011 failure of Martin Campbell's Green Lantern, which if successful would have surely paved the way for "Phase One" of the DCU being established. Instead, with a Green Lantern sequel and reboot both extremely unlikely, and various attempts to make Wonder Woman being delayed or scrapped, it's all up to Superman to try and jump-start the Justice League movie. Given how up in the air everything seems, and how much rests on Man of Steel's success, it really doesn't seem viable that the Justice League movie will ever actually get off the ground. So many of the moving parts just don't work, and even if they get Superman right, establishing the rest of the characters without their own standalone films is going to be a challenge.