Like... I'm pretty good with throwing kunai. That's one of the bases of basic weapons exercises in the academy. But here...

[Obito looks off in the distance, remembering.]

It's like, I know where to throw the kunai just right when I'm aiming at someone, and I can catch them right where I want to. But... it only works if I'm aiming at a person. You would think a moving target would be harder to hit, though.