Can join-up go wrong and what causes it?

Join-up can go wrong in several specific ways that reflect either errors in the trainer's technique, misreading of the horse's signals, or horses whose temperament or previous experience makes them respond differently to the process than the typical horse. The most common error is continuing to drive a horse past genuine exhaustion rather than stopping at the genuine submission signals — a horse that has been driven to exhaustion may appear to join up because it is too tired to continue moving, but the apparent compliance is physical depletion rather than social acceptance, and it will not produce the genuine following behavior or reduced flight response that characterizes real join-up. Driving too aggressively — pushing the horse into frantic, panicked movement rather than purposeful movement — prevents the submission signals from appearing because a horse in genuine panic cannot engage the social communication system that join-up works through; the signals require a horse that is processing and communicating rather than one that is running for its life. Misreading submission signals and driving the horse away again after it has already tried to communicate readiness to join up teaches the horse that its social signals are not being respected and produces increased resistance rather than increased trust. Some horses, particularly those that have been traumatized by previous forced training or that have extremely strong flight instincts, may take multiple join-up sessions before genuine social engagement develops — Monty Roberts acknowledges that join-up is not a single-session solution for all horses and that some horses require patient repetition before the full behavioral change occurs. Horses that have been shut down by previous handling may appear to join up without the genuine social engagement that the method aims to produce, mimicking the external behaviors without the internal shift that produces durable trust.