Finish is where you choose to end the motion of the stroke. It can even be before follow through for a short putt, or all the way up and round the back of the head with the shaft pointing at the target (Garcia style), or everywhere in between.
Some guys on this genious golf site once recommended to me, that I should hold the finish position at least until the ball lands or goes into the cup....it would guarantee a swing with good balance, and my computer would have time to evaluate and pick up all sorts of information about the motion I just finished.
If you don't program your machine from start to finish the stroke might throw you out of balance, make you bob, sway, break down the wrists, bend the planline etc.