Why is this "cycle" of story important in this novel?

Already in this first section, we see how McCarthy laces narrative structure, genre, character, and prose style together to give All the Pretty Horses its distinctive tempo and fluid style.

Each narrative section of All the Pretty Horses is organized thematically. The long first chapter of All the Pretty Horses can be divided into two parts - John Grady Cole emotionally distancing himself from his home in San Angelo, then John Grady Cole physically leaving it. In the first section he seems a confused sixteen year-old boy, at once cocky and awkward. In the second section, he is both reticent and deliberate - and very much a man. This structure is cyclical ending in a similar fashion to the beginning.