A lot of teenagers and below have zero humility. Arrogance can be useful to get you past the stage when you're terrible and don't realize it, to when you actually are good.

My daughter is learning HTML & CSS, as she's getting annoyed with copying and pasting headers.

Her work is ugly as can be, but she is totally in love with it and proud of it. Think back to early Geocities days.

I'm sure one day she will be embarrassed by her early work, but for now, she's enthusiastic and gaining useful skills.