If you've ever played chess, you know it's a very complicated game. If you want to be good at the game, you have to be able to look at the entire board, recognize a variety of possibilities, and see several moves ahead. An excellent chess player has to see all sixty-four squares and all the pieces on the board.
An excellent chess player won't move their bishop and think: "I moved my bishop there because it puts his king in check." Instead, an excellent chess player will be thinking: "I moved my bishop there because it puts his king in check, blocks him from moving his knight where he wants to, protects my queen, opens up space to move my rook, and sets me up to take his bishop two moves down the road."
When I'm watching an excellent chess player in a game, I can't possibly even guess their reasons for making the moves they make. But I know they've got plans that are wise and sensible.
In some ways God is like an excellent chess player -- except He's dealing not with sixty-four squares, but an entire universe. Instead of thirty-two pieces, He's dealing with billions of people. And instead of looking a few moves ahead, God is seeing the entirety of human history.
Sometimes we want to understand why God does the things He does, but as little as I understand why a chess player does what they do, I have even less chance of understanding why God does what He does. The Bible says that God's ways are not our ways, but it also says in Deuteronomy 32:4 that His works are perfect, and His ways are just.
It is fun sometimes to try to guess God's reasons for what He does, but ultimately we must learn to trust in Him even when we have no idea what He is doing.