While I do agree to an extent, a very wealthy uncle of mine has always told me "the hallmark of maturity is the ability to delay immediate gratification."
Is the life of a "mature" individual necessarily more worth, fulfilling, happy, or "successful" than that of an "immature" individual?
No, but a mature individual is more likely to make rational decisions leading to achievement of their goals.
Is the life of a "mature" individual necessarily more worth, fulfilling, happy, or "successful" than that of an "immature" individual?