Your first question may be “Why photograph public pay telephones?”
Public pay telephones are an artifact of the days before cell phones, and as such I want to capture examples before they are gone. However, I am also interested in factors which may lead to public telephones being installed and maintained in certain areas while they are completely gone in other areas. A number of public telephones have been found in locations with spotty or no cell phone service, including remote national parks. Others are found at travel-related locations, including highway rest areas and urban transit hubs. There also appears to be some correlation with demographics. Public pay telephones are often found in inner cities, possibly as a result of people who cannot afford cell phones or who are recent immigrants without access to cell phone service. Whatever the basis for their still being maintained, it is a challenge to predict where to look for these telephones, a surprise when they are located, and of interest to see their varying designs.