Will-power should be understood to be the strength of mind which makes it capable for meeting success or failure with equanimity.

Ramana Maharishi:  Your idea of will-power is success insured. Will-power should be understood to be the strength of mind which makes it capable for meeting success or failure with equanimity. It is not synonymous with certain success. Why should one’s attempts be always attended with success? Success develops arrogance and the man’s spiritual progress is thus arrested. Failure on the other hand is beneficial, inasmuch as it opens the eyes of the man to his limitations and prepares him to surrender himself. Self-surrender is synonymous with eternal happiness. Therefore one should try to gain the equipoise of mind under all circumstances. That is will-power. Again, success and failure are the results of prarabdha and not of will-power. A man may be doing only good and noble actions and yet prove a failure. Another may do otherwise and yet be uniformly successful. This does not mean that the will-power is present in the one and not in the other.