I want to be clear. Not all Dobermans are bad or weak. Some were poorly bred. There are dogs that come out of any litter that should not be bred. Breeding such dogs increases the chances of reproducing poor dogs in future litters. This can be producing undersized, excessive size, deafness, blindness , unstable temperaments, etc. 

I've had people come to me asking to breed to my stud. I had to turn them away. One recently did this. He showed my the pedigree. The dog was out of a well known a respected Presa breeder that specialize in working lines. I know the breeder. She has some good dogs. When I saw the dog I contacted her. She asked me to take the dog from the guy. She sold him the dog on a spay/neuter contract. He somehow falsified the papers. He's bred the dog a few times. I didn't take the dog like she requested. I didn't feel it was place to get that involved. But I do understand. This guy is giving her name and her kennel name a bad name. She thanked me for not breeding to that dog. My fear is that some other backyard breeder trying to make a few bucks will breed to it and use her name as a selling point. 

https://youtu.be/D1gCUs7alLE

https://youtu.be/QzPlSfnKANY

https://youtu.be/eS9mltHeeqU

Well bred dogs produce good examples of the breed.

https://youtu.be/wm5v--vvcVk

 Poorly bred dogs often produce deformed and or unhealthy dogs. Dog that can't perform, breathe, etc.

http://3milliondogs.com/dogbook/toadline-exotic-bullies-inbreeding-as-abuse/