Know your players. Improve monetization.
Make games people love.
Monitor how your players are moving through your game, what items they buy and which players monetize the best.
See where your players drop off and how long they stick with your game to improve the lifetime value of your players.
See where players experience problems and how much time they spend in certain areas; improve your game design based on solid data – not gut feeling.
Monitor your game in real time to see how many are playing it right now, and measure the quality of the game.