Time is the Ultimate Test to really delineate on Bust or Star Status. With that being said- The Spurs currently have 3 point guards that started in international play- Canada, Australia and France.
Parker is an All-World All-Star. He has been spectacular all year long.
Patty Mills really worked on his game this Summer and came into the season ready to play for the team and a contract. He seems to be playing back to his college days at St. Mary's except that he is passing the ball more and driving into the lane. I have been extremely surprised and most appreciative of his play during the Rodeo Road trip. Patty Mills could easily be a starter on other teams. He was the leading scorer of the Olympics in 2012.
Cory Joseph is still developing while playing the most difficult position on the floor. Most of Cory Joseph's floor time this season has been during the 4th quarter. Most Point guards take several years to develop and especially in the Spurs/Pop system. Look at Tony- in 2003, the Spurs made a trade deadline trade to bring in Speedy Claxton to help win their 2nd Championship. Tony was barely on the floor in 2003 Finals with Pop deferring to Speedy. Tony Spent more time in Pop's doghouse in those early years.
Cory has the benefit to learn behind Tony and Patty on how to be an All star point guard.
The Spurs Front Office is absolutely amazing. They acquired Patty Mills after Portland casted him off to Australia and before he became amazing at the Olympics. The Front Office hardly makes mistakes. They see Potential and try to work to make it better. Sometimes it works sometimes it doesn't however to label Cory Joseph a Bust without looking at the Team dynamics is erroneous and logically flawed. We as fans only see the game play and do not see the practices. When Cory was given the time (IE the D-league), Cory was an All-Star along with Nando De Colo. Last Year's Playoffs, Everyone was clamoring for Cory while screaming to trade Patty. We have fickle Spurs Fans- Cory has come in and worked- so much so that when the Front Office decided to trade the fourth PG they kept Cory and Sent Nando. Pop has probably forgotten more Basketball than anyone on this forum will ever know- if he is keeping Cory then it is for a reason.
The Spurs have an embarrassment of Riches- Hence you see First round picks sent overseas for several years developing and making bigger paychecks than the D-league. There are only 13 spots and 48 minutes for the team.
Trust in Pop and the Front Office- Cory Joseph is No Bust.