It's all a crap shoot
I think our expectations for the White Sox farm system get unrealistic at times.
I love talking about Sox prospects, but the fact is that the chances that any one player is going to develop into an all star is pretty slim. There are very few "can't miss" prospects in baseball (Prior, Mauer, B.J. Upton...) and where the Sox draft, they usually don't have access to those players. Even some "can't miss" guys do miss (Rick Ankiel, Josh Hamilton, Todd Van Poppel). And some guys look like misses their first few years then turn it on (Shawn Green's a good example.) Every organization has it's share of disappointments. Look at Cleveland. They have one of the best farm systems in baseball, but Brandon Phillips has disappointed, Jeremy Guthrie is a 24 year-old who can't get out of Double-A, etc. The Sox are not alone in having half or more than half of their prospects fail to produce.
Most prospects never become all stars. But it's still fun to speculate about potential. And on the whole, I think the Sox have gotten a better than average return from the prospects they've developed and acquired in trade.
In the last ten years they've developed Cameron, Lee, Ordonez, Crede, Rowand, Buerhle, Wells traded for Foulke, Garland, Olivo, Marte, Harris, and Uribe. A lot of their pitchers (especially Rauch) have been disappointments, but their home-grown position players range from adequate (Crede, Rowand) to very good (CLee, Cameron, Durham) to perennial all stars (Thomas, Ordonez). I'm sure a few of their top prospects are going to come up and suck, and other guys are not going to be very highly touted, but they'll excell. You never really know who's going to do what until it happens. That's what makes baseball so unpredictable and so much fun to watch.
Witness to the agony ('76 Sox season tix) and the ecstasy (2005 World Champions!)