Thanks for your feedback! There is no maximum speed right now. Mwahahahaha.
I made it get faster and faster so that the game progresses faster. If you only have 1 ball on screen, slow-medium speed balls would be near impossible to get past it. But if i lowered the AI speed , when there are multiple balls, the balls get past it too easily and player won't have enough time to consider their options. Not too sure how to do it without speeding up the ball, but I definitely should have a soft cap on the max speed.