Its because if the production rate is too high the cafe begins to flood. Also you can't control the milk production rate because it is on milky mode. My advice wile doing milky mode. DONT SPEND ANY MONEY ON THE MILK PRODUCTION RATE, THIS WILL MAKE THE PRODUCTION RATE GO UP FASTER WHICH IN THE LONG RUN MAKES YOU DIE IN A MILK FLOOD DUE TO TO FAST OF A PRODUCTION RATE.