Why are there two different openings for Nadeko in Bakemonogatari? In Bakemonogatari, there are two different openings for Nadeko - the one with a hat and the one without it.



Is there any specific reason why that is?
Studio SHAFT has almost a custom of changing openings even after they first aired. For example currently airing Mekakucity Actors have slightly different openings for their first 3 episodes, usually changing text fonts or scenes slightly. The reason for this is simply lack of time management, where they don't put much time to "quality check" the opening with director and they keep changing it until they like it.

That is probably case with Nadeko's OP. Someone of power simply didn't like the version with hat, so they remove it.