The 'Return to Normalcy' Ending

I am a large fan of anime, as well as graphic novels and books. However there a few storytelling methods that I dislike. One of which that I feel is unfortunately common in fantasy stories is the 'Return to Normalcy' ending.

It happens after the hero finally manages to succeed with whatever task he or she was trying to accomplish only to find that everything has returned to how it was before the task had to be accomplished. Worse the fantastical elements disappear.

Let me give an example. A hero from our world is summoned to a fantastical place where magic exists. A great evil has infested the world and the hero needs to go and defeat it. However once the evil is defeated the hero has to return to his world where he loses all the powers he has gained during his journey. To him it is almost as if the journey has never happened.

While oversimplified, the ‘Return to Normalcy’ ending is one of my least favorite endings because I feel that it makes everything that has happened before less important.