Despair is never a necessity for progress, it is always a sign of weakness and tamas; it often indicates the presence of an adverse force, that is to say, a force that is purposely acting against sadhana.
So, in all circumstances of life you must always be very careful to guard against despair. Besides, this habit of being sombre, morose, of despairing, does not truly depend on events, but on a lack of faith in the nature. One who has faith, even if only in himself, can face all difficulties, all circumstances, even the most adverse, without discouragement or despair. He fights like a man to the end. Natures that lack faith also lack endurance and courage.
Sri Aurobindo tells us that for human beings the degree of success in physical life depends on the degree of harmony between the individual and universal physical Nature. Some people have a will which is spontaneously in tune with the will of Nature, and they succeed in everything they undertake; others, on the contrary, have a will which is more or less totally out of tune with the will of cosmic Nature and they fail in everything they do or try to do.
As for the question of what is necessary for progress, in an evolving world everything is necessarily a help to progress; but individual progress extends over a considerable number of lives and through innumerable experiences. It cannot be judged on the basis of a single life between birth and death. On the whole, it is certain that the experience of a life of failure and defeat is just as useful to the soul’s growth as the experience of a life of success and victory; even more so, no doubt, than the experience of an uneventful life, as human existence usually is, in which success and failure, satisfaction and disappointment, pleasure and pain mingle and follow one another—a life that seems “natural” and does not require any great effort.
Ref : On Thoughts and Aphorisms