I think in most cases a suspect that is not confined in small area will not "stand still" when the dog is on them. I have experienced the suspect to "slow" down their movements when they have given up. On the other hand, a suspect that has made up their minds that they are not going to jail, will not likely stand still at any point absent other use of force options.
Although it is not trained enough, "outing" off of an actively resistive suspect is important. If the suspect were to be moving toward a body of water (ditch, canal, swimming pool, etc) I would want to be able to "out and recall" to prevent the drowning of my partner. This is one of several scenarios that entered my mind upon reading the initial post.