^Probably because they had to pay him so much.
Mo Williams and a winning record would be reason enough to resign. If he's set on going to NY then it's for someother reason aside from winning. They are doing fine now and can make some noise with who they have.
IMO He's the best player to ever play the game already, the only way to change the future is for him to die before he's 30. He will shatter records and there will be no question who is the best ever if he is healthy and lucky enough to finish his career normally! All I know is that he won't be in Dallas unless were playing against him..