There was a great show on PBS a while back, frontline maybe which described how hollywood has basically destroyed itself. It doesn't matter if the movie is good or bad as long as you can hype it enough to get high numbers on the first weekend, even if the numbers drop drastically after that. If you can do that, then you can make more money in the foreign markets, and since you can make more money in the foreign market than in the US, who cares if the American audience is happy? The plot doesn't have to make sense because for the most part the foreign audience couldn't understand it anyway what with funky translations etc. So as long as you have a good marketing team to build up the hype and lots and lots of explosions, you should make a profit, which unfortunately is all they care about.
C'mon, you knew it was goint to be terrible, why did you go see it?