Shouldn't have built a team around a chance to get a FA..
And besides, they chose Miami. Miami obviously had the best pitch, better than anything any other team could offer them, that's how FA works..you go to the place who puts you in your ideal situation, for financial reasons or other reasons such as winning.
They could've went to Cleveland and played, or Toronto and played, or hell even all 3 go somewhere else. So Miami simply offered something more, maybe a competent front office? Someone willing to sign help other than the big 3 and a coach who was a Pat Riley puppet>anything Cleveland, Toronto, or any other team had to offer.