We are told in the Open View that God may lose some battles, but he will win the war. But what is winning the war, according to the Open View? Is it that God does the best he can, and accomplishes some of his purposes? Then nobody ever lost a chess game, if that is winning, because everybody can do what they want on the first few moves, and we all will try and do our best. And then the devil wins too, by that definition, and even wins more than God, in some critical areas.
Also, God can lose every battle from now on, in all the areas where he has already accomplished some of his purposes, because he has already won, by this definition, and then providence, and sovereignty are practically zero from now until the end of the war, we may not hope for God to win any more battles in a given area, if he has already won one battle there.
Now if some will say that winning means winning the overall war, though losing some battles, then we just have the question in a different form: How minor a battle does it have to be, for God to be able to lose?
And if a battle can be lost, can’t they all be lost? How can the overall purpose be guaranteed, how do we know the roof will not fall, if the walls cave in?
And also, if the devil has a purpose to steal, kill and destroy, and accomplishes some of his purposes, then doesn’t he win some, regardless?
We may also ask what the overall purpose in the area of salvation is: To save as many as possible? But still only take whoever comes? Then God wins, no matter what happens, however, that is not most people’s idea of winning.
And finally, even after all is said and done, can’t saints in heaven sin, if each fully capable person has free will? Could not an archangel sin, and start the whole tragedy all over again?
Thus God could completely lose, even after winning, by virtually any definition.