There was more to it than that, however.
Bruce Arians, the Cardinals' first-year head coach, said limitations imposed by the 2011 labor agreement prevented him from getting a good enough feel for Kolb to consider continuing the relationship.
"The inability to sit down and watch film and talk football under the collective bargaining agreement hurt our chances," Arians said Tuesday from the NFL owners meeting at the Arizona Biltmore resort. "That made it hard for me."
Kolb was scheduled to earn $9 million in salary for 2013. His contract also carried a $2 million bonus due March 17 if Kolb remained on the roster at that point. The Cardinals released Kolb, whose contract will still count $6 million against the salary cap this season.
Cardinals general manager Steve Keim had a good feel for Kolb, of course. He was with the organization when the team acquired Kolb from Philadelphia before the 2011 season. Arians is the one installing the Cardinals' offense, however, and he'll be the one calling the plays. Committing to a quarterback sight unseen would be difficult.
The labor agreement prevents coaches and players from discussing football-related subjects until mid-April. Teams with new head coaches get a two-week head start on the process, but there's no meaningful on-field work allowed until weeks later. The Cardinals needed to move on Kolb by that March 17 deadline.
With Kolb out of the picture, Arians and the Cardinals acquired Drew Stanton, a quarterback Arians worked with last season while both were with Indianapolis.