Training Regression: Why Your Dog "Forgot" Everything They Knew
A dog that reliably sat, stayed, and came when called suddenly acting like they've never heard the word is one of the most common frustrations owners report, and one of the most misunderstood. It rarely means the dog "forgot" anything. It almost always means something changed.
Written by the TailorPup team, updated September 2026. See our editorial approach.
Adolescence is the single biggest cause
Most dogs hit a behavioral adolescence somewhere between 6 and 18 months (later for large breeds), driven by hormonal changes and a developing brain that is, functionally, more distractible and more willing to test boundaries than it was as a younger puppy. A cue that was rock-solid at 12 weeks can look shaky at 9 months, not because the dog unlearned it, but because impulse control and focus took a temporary step back while the rest of the brain develops.
The cue only ever worked in one context
A dog that learned "sit" exclusively in a quiet kitchen with no distractions hasn't actually generalized the behavior, it has learned "sit, in the kitchen." Move the same cue to a busy sidewalk with new smells, other dogs, and people, and the dog isn't ignoring you, it genuinely may not recognize the cue applies there yet. This is one of the most common gaps in training done casually at home, and it looks exactly like regression without being one.
A change in reinforcement history
If treats, praise, or play stopped following a behavior consistently a while back, the behavior naturally weakens over time, a normal learning process called extinction, not defiance. Owners often taper off rewards once a dog "seems to know it," which is exactly when many behaviors start quietly eroding.
Stress, health, or a change in routine
A new pet, a move, a change in the household, or an underlying medical issue (pain, vision or hearing loss, especially in older dogs) can all reduce a dog's ability to respond to known cues, sometimes overnight. If regression is sudden, total, and paired with other behavior changes (appetite, energy, sleep), a vet visit to rule out a medical cause is worth doing before assuming it's purely behavioral.
How to get back on track
Go back to basics briefly: high-value rewards, low-distraction environments, and short, successful repetitions to rebuild the behavior's reliability, rather than repeating the cue louder or more often in the situation where it's failing. Then re-proof it gradually across new locations and distraction levels, the same process used the first time the behavior was taught, just faster the second time around since the dog already has the underlying concept.
FAQ
Common follow-ups.
Is training regression permanent?+
No. Almost all regression resolves with a brief return to basics and gradual re-proofing across environments. Adolescent regression in particular tends to resolve on its own as the dog matures, often by 18-24 months, even with steady, unchanged training.
Should I punish my dog for "forgetting" a cue?+
No. Punishing a dog for failing to respond to a cue it hasn't actually generalized to that context, or one it's temporarily struggling with due to adolescence or stress, damages trust and typically makes the underlying issue worse, not better.
How do I know if it's regression or a medical issue?+
Sudden, total loss of previously solid behaviors, especially paired with other changes like reduced appetite, altered sleep, or reluctance to move, warrants a vet check before assuming it's purely behavioral. Gradual regression tied to a specific new environment or reduced practice is more likely behavioral.