When dog trainers talk about “fallout” we are usually referring to the unintended consequences that arise when training relies on fear, intimidation, pain, or other aversive techniques. These effects often appear long after a session has finished, quietly influencing a dog’s emotional well-being, behaviour, and relationship with their guardian. Yet the term itself is rarely defined in scientific textbooks, making it easy to underestimate how significant these consequences can be.

The idea of fallout was popularised by Murray Sidman in Coercion and Its Fallout (1989). Borrowing imagery from nuclear science, Sidman compared the behavioural side effects of punishment to radioactive debris: harmful, lingering, and easily spreading beyond the point of impact. He argued that these side effects often outweigh any short-term behavioural change achieved through force. In essence, fallout refers to the unintended lessons a dog learns when exposed to aversive methods.

A real-world example illustrates this clearly. Trainer and author Eileen Anderson (2025) described an obedience exercise in which handlers were instructed to give a leash correction if their dog moved towards food held by a man nearby. Her dog yelped at the correction, and although she refrained from going for the treat, she also avoided the man, hid behind her handler, and abandoned heel position entirely. The dog learned far more than intended: fear, avoidance, and loss of confidence. None of these lessons were part of the training goal but they became part of the dog’s behavioural repertoire nonetheless.

Research has repeatedly shown that fallout is not rare. Punishment frequently leads dogs to avoid not only the behaviour being punished but also the contexts, cues, or people associated with it (Azrin & Holz, 1966). In some dogs, avoidance escalates into aggression either directed at the handler or redirected to another target (Herron, Shofer, & Reisner, 2009). Generalisation is also common, a dog corrected near a doorway may begin avoiding not only that doorway but others with similar features (Hiby, Rooney, & Bradshaw, 2004). These are classic, predictable consequences of aversive control.

In some cases, dogs do not develop overt avoidance or aggression but instead shut down. They stop offering behaviour, appear subdued, and seem “calm” or “well behaved.” In reality, this is often a manifestation of learned helplessness, a state in which the dog has learned that their actions do not influence outcomes (Maier & Seligman, 1976). This emotional withdrawal is sometimes mistakenly praised as obedience.

Another form of fallout involves the development of compulsive behaviours such as tail-chasing, pacing, spinning, fly-snapping, or obsessive fixation on shadows or lights. These behaviours often begin during periods of conflict, frustration, or chronic stress. When a dog repeatedly experiences situations they cannot predict or control, repetitive behaviours can emerge as a coping mechanism. Initially tied to specific triggers, they may persist over time and appear in new contexts. Research shows that compulsive behaviours are more likely in dogs exposed to inconsistent, stressful, or aversive environments (Luescher, 2003; Moon-Fanelli, Dodman, & Famula, 2011; Tiira, Sulkama, & Lohi, 2012). Once established, they become resistant to change and significantly impact welfare.

Fallout also shapes the behaviour of humans. When a guardian delivers a correction and the dog immediately stops the unwanted behaviour, the person often feels instant relief. This relief functions as negative reinforcement for the human,an unpleasant emotional state (frustration or tension) is removed, reinforcing the act of punishing. Over time, this can lead to increasingly frequent or intense punishments not because they are effective in the long term, but because they reliably reduce the handler’s discomfort in the moment. This is an important behavioural loop, the human is being trained by the short-term cessation of behaviour, even when the dog is not learning in a healthy or sustainable way.

Some critics argue that positive reinforcement training produces fallout of its own, such as over-enthusiastic behaviour or excessive offering of actions. While these effects can occur, they are in most cases benign, temporary, and easily shaped with good training. They rarely involve fear, pain, stress, or damage to the dog–human relationship. The contrast with aversive fallout could not be clearer.

Modern behavioural research overwhelmingly supports reward-based methods as more effective, safer, and better for welfare. Dogs trained with confrontational methods are more likely to exhibit aggressive responses (Herron et al., 2009). Dogs trained with shock collars show increased stress responses, even outside training sessions (Schilder & van der Borg, 2004). Reward-based training is associated with lower stress and stronger attachment between dogs and guardians (Deldalle & Gaunet, 2014). A comprehensive review concluded that aversive training jeopardises both physical and emotional health (Ziv, 2017). Leading veterinary organisations internationally, including the European Society of Veterinary Clinical Ethology, strongly oppose shock collars because of documented welfare risks (Masson et al., 2018).

Taken together, these findings emphasise that fallout is not a coincidence, it’s an expected outcome of training that relies on fear or discomfort. Dogs subjected to aversive control learn lessons we never intend: to be fearful, avoidant, defensive, overwhelmed, or trapped. They may shut down emotionally or develop compulsive behaviours that persist for years. In contrast, reward-based training fosters confidence, supports emotional regulation, strengthens the relationship with the guardian, and produces reliable behavioural outcomes.

Dogs learn most effectively when they feel safe. When training methods prioritise trust rather than fear, the results benefit both ends of the lead.

References

Anderson, E. (2025, October 29). What do we really mean by fallout? Retrieved from https://eileenanddogs.com/blog/2025/10/29/what-do-we-really-mean-by-fallout/

Azrin, N. H., & Holz, W. C. (1966). Punishment. In W. K. Honig (Ed.), Operant behaviour: Areas of research and application (pp. 380–447). Appleton-Century-Crofts.

Deldalle, S., & Gaunet, F. (2014). Effects of two training methods on stress-related behaviours of the dog (Canis familiaris) and on the dog–owner relationship. Journal of Veterinary Behaviour, 9(2), 58–65.

Grohmann, K., Dickomeit, M., Schmidt, M. J., & Kramer, M. (2013). Severe brain damage after punitive training technique with a choke chain collar in a German Shepherd dog. Journal of Veterinary Behaviour, 8(3), 180–184.

Herron, M. E., Shofer, F. S., & Reisner, I. R. (2009). Survey of the use and outcome of confrontational and non-confrontational training methods in client-owned dogs showing undesirable behaviours. Applied Animal Behaviour Science, 117(1–2), 47–54.

Hiby, E. F., Rooney, N. J., & Bradshaw, J. W. S. (2004). Dog training methods: Their use, effectiveness and interaction with behaviour and welfare. Animal Welfare, 13(1), 63–70.

Luescher, A. U. (2003). Diagnosis and management of compulsive disorders in dogs. Veterinary Clinics of North America: Small Animal Practice, 33(2), 253–267.

Maier, S. F., & Seligman, M. E. P. (1976). Learned helplessness: Theory and evidence. Journal of Experimental Psychology: General, 105(1), 3–46.

Masson, S., de la Vega, S., Gazzano, A., Mariti, C., da Graça Pereira, G., Halsberghe, C., Leyvraz, A. M., McPeake, K. J., & Schoening, B. (2018). Electronic training devices: Discussion on the pros and cons of their use in dogs. Journal of Veterinary Behaviour, 25, 71–75.

Moon-Fanelli, A. A., Dodman, N. H., & Famula, T. (2011). Behavioural characteristics of compulsive tail chasing in dogs. Journal of the American Veterinary Medical Association, 238(5), 628–635.

Powell, R. A., Honey, P. L., & Symbaluk, D. G. (2016). Introduction to learning and behaviour (4th ed.). Cengage Learning.

Schilder, M. B. H., & van der Borg, J. A. M. (2004). Training dogs with the help of the shock collar: Short and long-term behavioural effects. Applied Animal Behaviour Science, 85(3–4), 319–334.

Tiira, K., Sulkama, S., & Lohi, H. (2012). Prevalence, comorbidity, and behavioural variation in canine anxiety. Journal of Veterinary Behaviour, 7(6), 268–275.

Ulrich, R. E., & Azrin, N. H. (1962). Reflexive fighting in response to aversive stimulation. Journal of the Experimental Analysis of Behaviour, 5(4), 511–520.

Ziv, G. (2017). The effects of using aversive training methods in dogs: A review. Journal of Veterinary Behaviour, 19, 50–60.