While a Horoscope is fixed at birth, there is also Free Will. A Horoscope represents the potential of life. While Astrology reveals our potential, Free Will helps us to achieve the potential.
Free Will means the choices that we make influence our future. Free Will is striving towards our goals despite the challenges, facing the challenges with determination, doing periodic reality checks, assessing downside risk of pursuing unrealistic goals, accepting accidents: physical, financial, emotional and moving on, understanding that we cannot change the past, our childhood, our parents and siblings, taking adequate precautions in problem areas of health, and most importantly, doing what is right.
Doing what is right (listening to the voice of conscience) helps in building up Credits and proactively doing what is right, results in a surge in Credits. Good Thoughts lead to Right Actions. As you sow you shall reap, results are embedded in the action, so tread on the right path and if you remain firm and intrepid, success will be yours!
Destiny is made up of two components: Sanchit and Free Will.
Sanchit is a record of past-life Credits & Debits, classified area-wise, so we get advantage of Credits, dependent upon benefic planets' placement and we have to repay our Debts dependent upon the malefic planets' placement. While Sanchit is fixed, Free Will is a variable which can influence our Destiny.