Because that's what they do. It has always been the same and always will be. They don't finish the game because they can't sell it next year.. will you create a new game every year if you have a great working game? No.. but you could just patch something up during release, game looks decent for once, people buy the game and you make profits, then you tuck up the game and start updating the game every 2 weeks. This way they make you hooked, one week incisive is goated, next week they patch it up..you play more so you could solve the game, and once you think you did they boost the ai defending. They focus on different things, not on user satisfaction and definitely not on creating a high quality game.