TFW Pokemon your trying to catch dodges everytime.

Nah, all random. I have fake threw a ball to test certain mons that seem to knock away balls all the time and sometimes they swing, sometimes they don't

It is all RNG.
Think of the gym lags, it is impossible keep up with everyone's tosses.
meaning, the mon's moves are predetermined. It RNG chooses from a library of possible moves.
Just like the popping off circle. It just happens, nothing to do with your toss timing.