The main reason is that horoscopes are like fortune telling. I can't necessarily disprove that whatever they say is going to happen... but the fact of the matter is that the words are just words. It is also an example of the Barnum effect, "the observation that individuals will give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically for them, but are in fact vague and general enough to apply to a wide range of people." Reading a horoscope supposedly tailored to them (their birthday in most cases), people will give high ratings and accept them. However, truth be told, they are general enough to apply to many people. It is all smoke and mirrors and illusions.
Hey, if they give whoever great joy and security in reading them, that is great. We need more joy in life, and these people can believe whatever they want. As for me, I don't believe in them and will place no trust in something like it. :)
kind of. i believe that certain people and it could do with when we were born, have similiar personality traits. For instance i am a Scorpio and any Scorpio i have met has many similiar traits to mine. but maybe its all in my head :P