I think what Kraco is trying to say is that, there's always something that's never happened before that has happened Naruto. Like, everyone knew what opening Gates would do to the body, and how Gaara always had an anger problem that manifested with the Bijuu. I might be wrong. But I bet all this happens because apparently, it's a new technique.

I agree with you in how Naruto's progress is always halted by some technicality or his stupidty rather than his failures.