In the dictionary of the seeker of truth there is no such thing as being "not successful." He is or should be an irrepressible optimist because of his immovable faith in the ultimate victory of Truth, which is God.
Jail-going is only the beginning, not the end of satyagraha. The acme of satyagraha for us would be to lay down our lives for the defence of India's just cause.
The sacrifice which causes sorrow to the doer of the sacrifice is no sacrifice. Real sacrifice lightens the mind of the doer and gives him a sense of peace and joy. The Buddha gave up the pleasures of life because they had become painful to him.