There was an immediate impact . About 367,000 consumers abandoned AT & T Wireless in the first quarter of 2004 , an incredible number given that cell phone carriers were enjoying unprecedented subscriber growth at the time . Like dogs suddenly let off their leash , consumers began a mass exodus from the notoriously unreliable provider as soon as they could . The exodus eventually brought the company to its knees , and it was forced to sell out to Cingular .