User blog comment:SeraphLucifer/Discussion/@comment-26992577-20151026232042/@comment-26992577-20151026234641

Yes that's probably the best explanation, it's mainly implemented this way for plot reasons and I think there is nothing wrong with it, keeps the show interesting. It's just odd from an in-universe perspective. However, assuming this is the last season, I would like to see the Darkness wipe out all the monsters, even the Leviathans.