Because Hit doesn`t seem to have full control of his ability (as evidenced by the fact that he literaly trained it while he fought), he has a 0.5 advantage let`s say every 10 second, the other 9.5 seconds, he is fucked. His fighting style is also totally predictable, it goes like this, goku is about to rush in on Hit, goku thinks "he`s so predictable i`m guessing he will try to hit my left shoulder", Hit stops times, analizes the situation, "where did goku move to? what kind of attack is he going to land? what are his blind spots? how do i counter it?" and finally he thinks, hey! let`s hit his left shoulder, he launches his attack but before the attack lands the .5 seconds are done and Goku with his SUPERIOR speed (kaio ken?) manages to block it.
In the end is all about the particular moment Hit activates his ability. If he activates it too early (my guess), his attack wont land in time and goku will be able to counter, if he activates it too late, he gets shat on. So yeah, he`s too slow. Hit`s ability seem to be more shock value, if he were just as strong and fast as Goku, it would be over, but he isn`t. As of now, he`s just a guy that is faster than goku in specific but painfuly short time periods that relies a little bit too much on his one trick pony ability and outside said time period, he`s nothing. Reminds me of Enel in a way.
Alternative explanation: It`s dragon ball.