When an author interprets a story he is bringing a new meaning to that story, adapting it to its culture, customs, values and ideals or the time when the author lives.
This reinterpretation is done to bring the reader closer to the work and to have an identification with the history and the characters.
Frodo has displayed going on the journey, for one, and also gathering up the courage to fight for his friends, the getting the mindset to throw the ring into the volcano
