Sometimes it's recommended they do.... My sisters dog is Great Dane and some other horse like dog when she adopted they said they can cut the tail and it won't hurt her but they decided not to and now she hurts herself from wagging it a much and hitting walls or hard surface. Not saying I agree with trimming it but if it's offered by a vet there's a reason to it. Just like dogs with long tongues.
Like mizu said, many larger dogs injure their tails a lot by banging it into things. Many other dogs are docked (tail cut off when they are puppies) for health reasons or if they are a hunting dog, to prevent burrs and stuff to collect on their tails, which could end up puncturing them and causing an infection.
It was much more common years ago and many countries actually ban it today, but its still a very common thing in many breeds.
Somewhat similar to circumcision on human males, for the most part it is completely cosmetic and unneeded, but it was still based originally on medical reasons.
It was much more common years ago and many countries actually ban it today, but its still a very common thing in many breeds.
Somewhat similar to circumcision on human males, for the most part it is completely cosmetic and unneeded, but it was still based originally on medical reasons.