Vulgar taste is cheap, but good taste requires, in my opinion, a great deal of exposure and study to develop, and even then also requires "an eye" i.e. innate talent.
There isn't a difference there in my experience. That "eye" is the taste, and before you start studying/practicing/training/doing - most of the time you won't know the "why it works" either. I'm not sure what "vulgar taste" would be.
Vulgar as in plain, common
the secret sauce here is talent, if you don't have it you'll end with an entire internet full of purple rounded buttons