Board Thread:Theories and Speculation/@comment-3001903-20151205022433/@comment-734582-20151207103510

GreatestSin wrote: it is possible that kishi didnt have this whole "sage body"/"sage eye"-story while writing that part, or, it is simply because obito is far more powerful with kamui than 2 rinnegans ^_^ Or it's much harder to master an eye than just slapping it in your eye socket. Kakashi could barely handle the Sharingan originally, but through training could eventually use Mangekyou. I think the same applies here: Nagato had plenty of time to master his eyes. Obito didn't.