The article says it's Carlos Slim's company that was ignoring the village because the population was too small:

"After being ignored by a company owned by the world's richest man Carlos Slim, a tiny Mexican village has developed its own mobile network with international connections."

"The village of Villa Talea de Castro, dotted with small pink and yellow homes, has a population of 2,500 indigenous people. Tucked away in a lush forest in the southern state of Oaxaca, it was not seen as a profitable market for companies such as Slim's America Movil. The company wanted at least 10,000 subscribers to bring the village into its mobile coverage, AFP said."