Why do tails of certain breeds are cut?

I have two miniature poodles and both still have their tails I am pleased to say. Photos and pictures of poodles in the past have cut tails. I know that the Kennel Club used to want particular looks from each different breed of dog. I think they don't require cut tails on poodles these days. Cutting off a dog's tail would be cruel and cropping the ears would be equally as cruel. Poodles look great with tails. I am an animal lover and I like to see animals treated with kindness.

I remember once I had a Boxer at home and the day my dad brought it home my brother wanted his tail to be cut just because he will look very fierce and people will get afraid of him and because my poor brother thinks that this is style, I was and I am still against that because the dog would have to suffer so finally my dad did not allow the tail of the dog to be cut, I was so happy. People say that to cut the tail of these dogs will decrease their temperament, I do not like that because the dog will suffer. I once told my brother that we will shave his long and beautiful hair because to shave is style and he then understood that it is not good to do such things just for styles to dogs and they cannot oppose too because they do not know how to talk.