Wars between civilizations should have clear motives

I think kingdoms should make specific cities for seperated purposes. And that they should fortify the important cities (like the capital, mining towns, and trading ports). These key cities would also be prime targets for invasion and could lead to some interesting possibilities. Like if a country's main trading port was taken and now they can't import food, materials. Or if they're mine was conquered and their army has to fight using only sticks. This also means that wars would have a winner, that being the country that took the most key places. Currently wars just feel like throwing to countries at each other and the one that survived was the winner, but more technical victories are an interesting concept that makes the world more immersive. (Ex. Country A lost 4 villages and 150 soldiers but took country B's port and burned the farms in their agricultural area, while Country B only lost 1 city and 100 soldiers but gained 4)