I don't believe it's anyones intention for dogs to end up in shelters, even breeders. Just like when parents have children, I'm sure it's never their intention to breed criminals - but it happens. Unlike humans though, dogs often aren't provided an environment where they can make choices we want them to make. They're left to fend for themselves, then get blamed and in trouble for acting like a dog - humans get frustrated, then they take the dog to the shelter attaching labels like "My dog it aggressive and dominant, I can't deal with him (or her) any more."
What can be done? Prevention and Socialization!!! Sure, puppy training classes and basic dog training classes are great, but it needs to go beyond the basic 6-session dog obedience class. Just like humans go through a multitude of developmental stages, so do our dogs. It doesn't stop at just one class.
- Teach dogs behaviors they need to exist in our human world. And continue reinforcing those skills learned.
- What items to chew on and when.
- How to be alone and entertain themselves through enrichment programs designed for dogs.
- Meet and greet hundreds of humans while they're young pups, and again continue allowing them to meet new people, in different places and in different situations.
- CONTINUE socialization during adolescence so they can continue learning and adapting to their environment.
- Understand what normal behaviors are for dogs.
For many of these dogs it's the environment they are born into, and are raised in, that is often the cause for the issues that land them in the shelters - so again this falls back onto the shoulders of the humans that have the most influence over them and their quality of life. I only wish that some day there are universal training protocols, "Gold Standards" if you will, for dog training. Until then it's wise to be critical thinkers, use common sense, and plan for how to raise a healthy and happy dog in order to keep them out of the shelter.