T-Mobile (NASDAQ: TMUS) has become the fastest-growing player in the wireless space by aggressively pointing out the faults of its rivals. CEO John Legere has made it his business to not only use his company’s merits to win subscribers, but also to expose industry practices that are not consumer-friendly. That has put both AT&T (NYSE: T) and Verizon (NYSE: VZ) in the maverick leader’s crosshairs, and he has been a convincing figure to consumers.