There's the Calvinist way. Evil exists because it glorifies God (at the everlasting expense of his own creatures).
And there's the Universalist way. It was always God's intent to forge men's characters in the furnace of affliction and part of this purging process—this education, this discipline—is the battle with evil—a battle that will terminate with all of humanity being made into the image of God.
What does the rest of Christianity think of the Universalist way? In The Problem of Evil – A Theistic Theodicy, Grace Communion International examines the various theodicies employed by Christians. It breaks them down into four categories: Process Theism, Free Will Theism, Theological Determinism, and Soul-making theodicy. It's the last category that applies to Universalism. Here's what they had to say about it.
“Although soul-making seems to be close to being a biblical theodicy, there are some assumptions that may not be biblical after all—for example, assumption “c.” The conclusions would seem to support Irenaeus's theodicy, which calls for all men and women to ultimately experience redemption by God. Although it is biblically true to state that the Lord is “not wishing for any to perish but for all to come to repentance,” it is also true that man's mind without Christ is by nature hostile to God, and for some people, the results of evil will be utter rebellion and hatred.”
Back to the drawing board.