Right quickserving isnt necessarily cheating, it's just one of those things that we could argue is frowned upon or a form of sportsmanship, although I believe most people would agree that it's somehow undesirable. (I dont see anyone on here fighting for their right to quick serve)
The problem with it is that there is probably a gray area of when you are really ready or not. If you're used to getting into your stance and getting a few seconds to look at the server, clear your mind or whatever, then you might feel that a serve shooting out instantly is too soon.
The rule mentions about you "being ready", but it doesnt really say what that means because we dont typically say or so anything to indicate we are ready other then get into our stance.
That's why to remedy the situation, it's suggested that you hold your hand up until you feel you are ready, that way you ARE signaling that you are not ready and if they serve before that, you can say with 100% certainty that you were not ready.
