A friend of mine once told me that he felt guilty, because he wasn't successful in a worldly sense, and therefore was "not a good witness" to his worldly parents and brother, who didn't respect him.
He was very gifted, but somehow things didn't turn out, and he was still struggling to find his place in his mid 40s.
I told him that he shouldn't think that. Being successful at a worldly career is highly dangerous to the soul. It is more difficult for a camel to pass through a needle's eye, etc.
I often think that what appears to someone as failure is really a providential mercy, necessary for their salvation. God loves the poor, and the sick, and the miserable. And when He comes into the world it is they who accept Him.
The important people at the time of Christ rejected him. It was the lame and the blind, the tax collectors and prostitutes, the poor and miserable who accepted Him first.
Of course nothing is impossible to God, and so even "successful" people can be saved. But one should never let worldly failure lead one to despair: Perhaps *for this person* it is necessary to be humbled in this way in order to be exalted for all eternity.