Respecting free will is Gods greatest love.

Lucifer could sin, man could sin.

But its still freewill. And God respects that even if he knew Lucifer would tarnish that gift.

People always say "why does God allow evil if he's so great?"

Well if God always intervened that would be the greatest cop out in existence.

Example. If you always gave into your child's demands the child wouldn't grow, but become a dependent.

This is what is happening to the world right now, no one wants to take responsibility. People are too dependent on the system that's why this place is getting eviler and eviler by the second.