It is true that the science of Astrology is a science of indication. Provided there is a strong will and requisite effort is brought into play, certain indications in the horoscope can be overcome. Of course, the strong will in such a case will be indicated in the nativity itself. Just as unfavourable indications can be overcome. In the above manner, the promise of good effects can also be spoiled in various ways. A weak and vacillating mind will not be able to take advantage of the planetary vibrations and brings them to fruit. For example if the man acts perversely, he can prevent a good alliance of marriage. It is to some extent within the range of prediction too.