I think what he's saying is that Migs is shitte and has proven to be over three seasons. Karius has had 10 games which is no time to settle and be able to make an informed judgement.
I think he's made the right decision in taking Karius out of the firing line!
I'm also interested in the responses of certain posters who have been calling Klopp stubborn, etc. He's picked Klavan at centre half instead of Lucas as well.