Why is the animation so lazy af?

Seriously, one of the laziest animations ever, especially for battles. We don't get fully fledged fight scenes. We see Kunai launch an attack in one frame, and then the next we see almost a freeze frame of the attack landing on the enemy and them getting damaged. I feel this was a lazy, half-assed attempt at animation, like they brought in an intern and had him do all the battle scenes.