Before a dog is ever entered for a competitive show, there is a lot of work that must be accomplished in order to be able to present the dog properly. There is nothing like having a quality dog that is unprepared for a show. A dog that hasn’t been well trained and conditioned just won’t be a competitive dog.
Everyone is familiar with sit, down, and come and other similar commands that are standard fare in the general obedience training class. The novice handler might not be familiar with what competitive obedience looks like or realize that it’s really just a continuation of those basic skills.
For the health and wellbeing of your dog, training should really not ever be considered an option when owning a dog. Well trained dogs are more likely to be behaved and listen, be void of behavioral issues, be good in public, and are less likely to bite. Owners also have a much closer connection with the dog when the time is taken to form a relationship through training.