10 Harry Potter Theories You Won't Be Able to Wrap Your Head Around

Neville wasn't the greatest wizard in the books and ended up fumbling plenty of spells. But as one theory suggests, it's all because Neville is using his dad's wand. We're told in the first book that the "wand chooses the wizard," and Neville never had that opportunity until after Harry Potter and the Order of the Phoenix. After that book, Neville had his own wand and became a stronger wizard with it.