The main reason for using a readmore is for those people who either browse the front page or browse the sections where node contents are shown with the readmore content collapsed. That allows readers to get an overview of a node without being swamped by a huge wall of text. This is particularly effective for meditations where the body of the meditation is tucked away in a readmore with a brief introduction shown in the section view.

There are many ways of using this site. readmore is designed to make it easy for people who browse using the section views, but doesn't make any significant difference for people who read threads (accessed using Recently Active Threads for example.