The Cards had a good 3 years to work out a long term deal with Dansby and didnt make a real effort until he had gone to Miami to get a real offer. If you want to be angry about the way he left then blame the front office.
Didn't make a real effort?
There was a deal done; it was announced to the media that the Cardinals and Dansby's agent had reached an agreement. Dansby refused it and fired his agent! The timing of this firing was such that there was no way an agreement would be reached prior to Dansby's second season under the franchise tag.
Contract negotiations are conducted, in almost all cases, between the club's front office and the player's agent, not the player directly. Is it the Cardinals fault Dansby and his agent weren't on the same page?
From my perspective it appears that Dansby was the one that didn't make the effort to reach an agreement!
Obviously, it is well within the player's rights to want to play elsewhere and to take the necessary steps to make that happen. That is exactly what Karlos Dansby did. He didn't want to remain with the Cardinals, simple as that.