It means that you didn't specify the pin length or top weight when placing your order. Pin length and top weight can affect the options you have when drilling the ball. However, if you paid for a top-quality ball (and not a blem, 2nd, X-out, or pro-pin) then you should get pin length and top weight that give you plenty of options when it comes time to drill the ball.
You probably should have consulted with your pro shop ahead of time or at least thought about what kind of reaction you were looking for. That can influence the pin and top weight you order, but not so much as to make a "random PIN" ball undrillable.
SH