T-Mobile (NASDAQ:TMUS) has undoubtedly made some disruptive moves in the past year. The first big move came when the company did away with contracts. But it's T-Mobile's most recent move that really highlights just how aggressively the company is trying to acquire new customers. The strategy is clearly working. In the company's fourth quarter T-Mobile added about 870,000 new net postpaid customers. But the big gain in customers came with a cost.

As T-Mobile aggressively pursues new customers, it is facing two major challenges: costs and demands for better service. In the following video, Fool contributor Daniel Sparks takes a closer look at these challenges.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.