The essence of human experience is to struggle. It is only through struggle that we find cause to mature, to acheive, or to create. Advancement is driven by pain, growth is part of the healing process.
Even the classical conditioning of labratory animals can bear this out. Given rewards over and over again, an animal eventually is jaded by the reward, the conditioning diminishes in effect because there is no return for the act. But pain will ensure a well-embedded behaviour for life.
The human experience is more sophisticated by several degrees of magnitude, but remains in essence the same. A man clings to pain, it alters his perceptions, closes him down, builds walls around him that restrict intimacy ad trust. In the end the pain of lonliness outweighs the pain of experience, and the man must seek to put the experiences in the past and take only what he needs.
What fools is it, then, who seeks Utopia or some Aristotelian "good life" free of pain and suffering? A life ideal for living in comfort and ease in order to leave room for greatness is folly, because greatness comes from the flaws of our life. If we had everything, then we would stand to gain nothing. Heaven as it is formulated by most is the cessation of growth. To want nothing. To withdraw from the world.
Certainly, the Utopian sleeps easily, but life is not for sleeping away.
And that is why humanity will never accomplish it. It is not part of our programme. Utopia would signal the end of worthwhile human pursuit. Every age is full of flaws and struggle because that is one of our greatest needs. The universe is a sine wave of pain and growth. We understand this with every cell of our being and everything we express is flawed in reflection of it. We create strife because it is something we need.
The outrage and fire in the belly necessary to chase perfection sustains us. actualy catchin perfection would mean our annihilation.