Sometimes a science fiction or fantasy story makes a logical error so egregious that you can't let it go. Even years later, it still pops into your head and annoys you. Why did they DO that? Tell us what stories make you feel that way.
My pick is a pretty obvious one. How did Darth Vader not realize that Leia was his daughter?! It's not like she was hidden on an obscure farming world. She was right out there in the open.
You can pick a comic, game, book, movie, or TV series. Anything that has a logical inconsistency that you are still kind of fuming over. Tell us why it stuck with you, and share pictures, video and links too!