The Great Controversy

Lucifer accused God in heaven. One third of the angels sided with him; while the rest remained on God’s side, yet with questions. Therefore God, who knew where Stan’s system will lead, allowed him to demonstrate what he is about, that intelligent creatures might see who’s right and who’s wrong.

Our world is a classroom, and Satan the god of this world. If God solved every problem on Earth, we will have a mistrial, and evil will not be seen. Solving every problem will tamper with the evidence.