I don't know he was just so annoying.
It's not like the characters had a happy childhood either,yet he was the only one who was costantly full of hate and seeking for revenge.
I found him a bit boring.The only moments I could stand him it was when thank to Naruto's good energies he was a bit less uptight and more lightened.
[sp]And then he killed Itachi,a character I really found interesting.[/sp]