Hyperactive! Out of control! Impulse issues! Reactive! Lacking self control! The labels are readily applied to so many dogs, yet the handler often isn't even considered to be part of the dynamic that contributes to the dog's behavior.
One huge problem I see over and over again is that handlers often silently permit the dog to do as he pleases. Handlers may have quite a dialogue in their heads going on in their head at any given moment: