Although Harry Potter is descibed as an amazing kid, many fans noticed that it's quite the oposite.
As we all know, Harry was not very smart. In the first book, Harry got many letters. The first one gor straight to Harry, and instead of hiding it or even reading it in the hallway- he brought it to his uncle. But at least he conffesed that that was a mistake. Later on, when the letters filed the Dursly's house, Harry jumped and tried to grab a letter from the air, instead of doing the most obvious and logical thing: picking one from the floor.