Have you seen that movie? It is just unwatchable.
That's because Lennon and Garant, the writers who were hired to write the movie, got fired after they'd turned in their first draft. According to their fantastic book, Writing Movies for Fun and Profit, they had pitched their take on the script to one studio head, who loved and subsequently bought it. When it was time to hand in their script, they were told to give it to a different studio head, one who didn't get the script, so he told them to make a number of changes, which they did. Then the original studio head came back and (rightfully) said, "Hey, this isn't the movie we discussed; you're fired." Then NEW writers were hired to "fix" it (these writers likely won't be mentioned in the credits, by the way). Then those NEW writers were fired by a DIFFERENT studio head, and ADDITIONAL writers were brought on, with a focus on pleasing some OTHER studio head and not getting fired.
Here's a visual representation of the whole process.
That's how a movie like Herbie: Fully Loaded happens. That's how Amazing Spider-Man 2 ends up feeling like a sprawling, scattered mess (one writer was hired, then fired, and two additional writers came in to fix it, where "fix" means "add a giant clock tower in the middle of an electrical factory because we already bought the clock tower and there's no return policy"). That's how Last Action Hero was never totally sure if it was an action movie or a parody of action movies (it went to at least nine different, mostly uncredited writers, including Carrie Fisher for no reason). That's how MOST big summer movies happen. Writers get fired and replaced constantly, and every new writer has a different agenda; maybe they're trying to please the studio, or maybe they're trying to focus on their own artistic vision. It doesn't matter. The point is that a movie that used to be the execution of the vision of one or two people is now suddenly the execution of the vision of a team of people who have never met and who have different goals and one of them might be even Carrie Fisher and some of them were almost definitely drunk when they made their rewrites.