8. It's Not Set In The Man Of Steel Universe
Supergirl seemingly being in a separate world to Arrow and The Flash and the fact that there was a huge Supergirl Easter Egg in Man of Steel has led to some speculation that the series might be set in the DC Cinematic Universe. It's a nice theory and some fans will no doubt try to find some ties between the two, but it's obvious that they're not connected. From impossible to miss visual differences (Krypton doesn't look remotely the same as the Man of Steel version) to timeline issues which mean that there's no way this could even be set years after the events of Zack Snyder's movie, Supergirl serves as a stark reminder that DC's shared universe plans only stretch as far as their big screen projects for the time being. However, it not being set in the DCCU, doesn't mean Superman doesn't appear though...