reasons for failure of predictions

100% people are not aware reasons for the failure of predictions. Simply they throw the mud on Astrologer. Even some times ; most of the Astrologers are confused why their predictions got failed.
1) Time of birth : Accuracy of Time of birth plays key role in failure of predictions. If Lagna gets changed with change of time of birth from 1 minute to 10 minutes ; astrologers shall inform the same to the native and correct time should be fixed as per the past, present life events of the n