How does the creation and study of a Guru's biography like the Shri Sai Satcharita help in fostering a community of devotees?

According to the preface in Chapter 0, a Sadguru accepts service through books by having devotees write his biographies. When a devotee writes a detailed biography, they perform Guru service. This service then extends to the entire community when other devotees study and perform Parayans of that work. This shared practice creates a congregation focused on the Guru's life. The text states that through this collective engagement, the writer gains the merit of serving God in humanity (Jan-Janardan), and the other devotees also achieve the purpose of their lives, thus building a strong, spiritually-focused community.