The Cure is Worse Than the Disease.
Among the services offered by many trainers, "behavior correction" is often one of the top options. I can confidently say that this service is primarily used by those who don’t want to bother with proper training and education of their dog. Such clients seek a quick fix to "problems" through behavior correction.

Pulls on the leash—correction.
Doesn’t come when called, picks up food on the street—correction.
Barks at passersby and animals—correction.
Chases cars and starts fights—correction.
Climbs on the table without permission—correction.
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These "owners" believe that the dog MUST behave correctly, that it’s being disobedient on purpose and acting against the owner's will. But they never stop to ask themselves, what have I done to make things different?