Why are some dogs so vicious?

video games
rock music
and tv
For many reasons. The way they were raised. Being in small places too long. Mistreated.
mainly depends on how they are treated by the people around them. Any dog can be mean or vicious no matter the size.
We had a vicious dog once. He was vicious because my father was target practicing when he was drunk and accidently shot the dog in the leg. That'll do it! My best friend has had 2 vicious dogs. My daughter says her dogs are vicious because they are big dogs in a small house that are not let out enough. They never get to run around like they need to and that makes them vicious. Those are just a couple of ideas. I'm sure there are more.
All the same reasons some people are.
Hi, No dog is born vicious, its all down to the wrong treatment when they leave their mother. It can be a cruel owner or simply not being taught the proper behaviour. Its the people who have dealings with the dog throughout its life.
All animals can be vicious. It depends on how they are raised and how they are treated. I have 2 rotts and they are the most lovable and affectionate dogs I have ever been around.
It depends on the owner how they bring them up
I truly feel that owners make a dog vicious. If a dog is treated with much kindness and respect, yes respect, payed attention to and LOVED!, they will reciprocate. In some cases if a dog is inbred too much that can lead the animal to become what we would call crazy
it's usually the owners fault!
these people shouldn't even own a pet
yummygoods answer has had me laughing so much i have a shitty cold and its a really tonic thanks xx
dogs can be vicious by there very nature like say the Chinese (i think it was them my history is rubbish) well did you see dear hunter? they are mad men oh year the dogs yes some of them are just mean mean mean i have been bitten twice
well if you were put out on a chain and discarded like some old toy you'd be a bit peeved as well. Its all on the up bringing. How you introduce them to people and how they interact in your family.
neglect mistreatment.no dog is born vicious ..its the way some people treat them.the only time a dog is vicious for no apparent reason is if it has a brain tumour otherwise man made it that way...
Because some where trained by owner or the are not house broken.They need to be house broken because they think that you are tring to hurt them so they portect them selfs.
Some dogs are so vicious because of the way they have been trained by their careless and stupid owners. Some dogs are not socialised properly as puppies and this can cause problems. Some dogs are mistreated by their owners and react out of fear.

Some dogs are a bit vicious as a natural trait in their characters, this can be controlled though through appropriate training, treatment and guidance.
i agree with the first answer from sunflower
I was given a schnouzer about 3 yrs ago when he was just a lil puppy. When he started to get older he started to get mean. He would bite at ppl's feet (only men) and my cousin told me that the reason he was mean like that was b/c the ppl that had him would lock him in a room and kick him, and that made him mean. When guys would come over to the house we would have to put him up in a different room so he wouldnt do anything to the ppl that were coming over. We have talked to the vet and they have told us that sometimes getting a male dog fixed will make him less mean.
badly bred (from 2 parents with bad bloodlines or from parents who were aggressive) or because they have been miss handled, trained to be that way, or confused
maybe because they might have been mistreated or didn't get socialized as a puppy.
Some dogs have psychological problems which only manifest themselves under certain circumstances- much like people who end up in mental hospitals etc, animals can be exactly the same. Also just like humans, brain tumours etc can make a dog completel change behaviour and be very agressive. There are lots of reasons.