AT&T is not a great cellphone service provider. Recently, Consumer Reports reported that of the nation’s major carriers, AT&T is the worst carrier in every category (service, data, customer support etc) in nineteen out of twenty-six cities surveyed. In the study, Verizon was the overall winner.

Neither result is surprising. The iPhone is a fantastic little computer, but its service can be laughable. Whenever a friend of mine switches from Verizon to AT&T, I realize that my days of talking to him or her on the phone are numbered. My iPhone-toting friends and relatives’ voices won’t come through clearly; they’ll drop my calls, and there are whole neighborhoods where their phones won’t even ring. But how much does network quality really matter? Here’s why AT&T will continue to have a strong, devoted customer base despite shoddy service and high prices — as long as it has exclusive rights to the iPhone.