Why does my dog scratch at the door when left alone?

Scratching that happens immediately as you leave, especially at the specific door you exited through, usually reflects distress rather than a genuine need to go out, since a bathroom request would not typically be so tightly linked to the moment of your departure.

Persistent scratching can wear down claws, damage paint or wood, and in more severe cases lead to bleeding paws or broken nails, which is one of the clearer signs that distress has crossed into a level needing real intervention rather than being left to fade on its own.

Blocking direct visual access to the door, practicing calm departures with very short absences, and rewarding settled behavior away from the door all help. A textured mat or scratch friendly surface placed elsewhere in the room sometimes redirects the behavior while the underlying anxiety is addressed.

A clear plastic guard over the lower part of the door, or a sturdy mat covering the area the dog tends to focus on, protects the surface from further damage while training progresses. This kind of temporary protection is a sensible management step, not a substitute for addressing the anxiety itself, but it does prevent an ongoing cycle of damage that can be discouraging to see day after day. Removing the protection once training has genuinely progressed, rather than leaving it up indefinitely, is a good marker to check periodically for whether the underlying issue has actually improved.