Astrology works with the exact moment of birth, the beginning of a situation or when someone asks a question. At that moment the astrologer symbolically stops the time and calculates a sky map also called an astrogram.
Astrology can be used to define human character, human psychology, his talents but also weaknesses. It can answer certain questions or calculate the best time to start something new. Astrology does not foresee the future, but may give clues to future trends.
Each person is unique because each birth takes place at a unique moment in time and space. Even for two people born at the same time and place, if they are born a few minutes apart their astrograms will be different.
I do not think that annual horoscope can accurately define the future trends of each individual. Moreover, a natal astrogram must be interpreted according to the level of consciousness of each one. Planetary transits give influences that we feel in our lives, one more than the other and each in its own way depending on its natal theme. Making a general prognosis that fits anyone is a utopia. Each of us must decide what fits him in an astrological forecast, with what he resonates in particular and especially with what he does not.