Aside from the theme song, I don't think there's a line I identify more with the Harry Potter franchise than Robbie Coltrane as Hagrid saying "You're a wizard, Harry!" It was used in so much promotional content. I heard it over and over again. And it's a great line. I tells a new audience to a new franchise what the story is about. This kid over here? He's a wizard and he didn't know it. Let's go have some hijinx!
Perfect. So what's the problem? Well, the kid who doesn't think he's special discovers he's extra special! is a pretty established trope in children's fiction. Hell, it's pretty frequent in adult fantasy/sci fi as well. Big things in little packages and all that. Oh no, I'm crippled! or No one likes me! or whatever and then bam, I have magic powers that more than compensates for any shortcoming I previously had (often erasing that shortcoming in the same stroke).
As with all my other writing, I am
of these kinds of things. They're not bad, not necessarily. They can still be awesome if the writing is awesome, but we've seen it SO many times. You're a wizard, Harry!
So here I am writing my first middle grade fantasy, and I make sure I have a completely mundane main character. His name is Mirza. He works in the stables as a groom. You know what? I'll go one better. He's a runt. He's small for his size, has trouble handling the horses, and the other grooms don't like him. (This should have been my first warning because now I've given him a deficiency to overcome.)
This was the character that was going to save the shahzadi. He did not have magical powers or any kind of special skills. He wasn't a thief. He wasn't a fighter. He knew how to raise cats to be good mousers and he got beat on by his father and the other grooms, so he was tough but psychologically scarred. And that little guy was going to have to do great things!
...but as I started writing, a whole sub-plot with Mirza's mother surfaced that I had not even thought of. My original plan was Introduction > Inciting Incident > Action > Resolution > The End. Somehow > Character Development snuck in there and all these things happen that I had never planned to have happen and a character says, "You're a wizard."