Well yeah, kinda shocking to see them out so early. Especially after they owned every team at qualifiers, but since test game they played totally rubbish. But you know there are can be many reasons for that to explain.
1) It's not a first time already, that ex-Champions dropping out in the Group Phase. It happened to Italy and Spain already exactly the same way before. I think the main reason for that is, when you already have been on the top 4 years ago, you are not so ambitious for the next time anymore. It's in a human nature.
2) Most of the players of the German team meanwhile are pretty old for Football, the most of them are close to 30. It's sensitive difference to 4 years younger team at 2014.
3) Short before WC there been a huge scandal around stupid Twitter Fotos made by two players of German National Team Mesut Özil und Ilkay Gündogan, who made this Foto below and then brought it to the public. It brought a terrific dissonance from society and fans and hammered hard on morality of the whole Team, who has nothing to do with this. Even Manuel Neuer wrote in his Twitter those time "All this Story and dirty comments from society are really burden for the whole team, which they need least of all at this moment." I think it was really stupid and ugly doing that especially short before WC starts. First of all it's known that absolutely the most (intelligent) population of Germany think that a big part of Recep Tayyip Erdoğan's politic is really bad for his country and for people. Some of even calling him a dictator. It's also known, that a biggest part of population with foreign background are coming from Turkey. And there is another problem, that some part of them are supporting mr. Erdoğan, which often brings conflict inside of German society. And you go there meet him and make this Photo, with your Football Shirt, you will be wearing while playing for Germany?! I mean what the hell is this. I mean, i respect political tastes of anyone and they of course allowed to meet anyone anywhere, but please keep such photos in you private folder on computer and not make it public, if you are not going to move and play in National Team of Turkey. Otherwise it's a pure provocation, which it was. Of course it's not a justification of a bad play of the German Team, but had to mention it, as it was a big impact to their morality before the games start.
And 4) "The Outsider Teams" are simply became much stronger. Just look at other games nearly every "Favorite Team" had to struggle a lot. Spain, Brazil,
argentina, England, you name it.. They all showed us not the best form and there were no "easy games" for them too. But it what makes WC Championship to such a stunning show, it's just impossible to say what happen next and who will be on the top this time! Enjoy your watching!