Conversation so far:
What is a librettist?
A librettist is a writer of a libretto.
What is a libretto?
A libretto is the text used in, or intended for, an extended musical work such as an opera, operetta, masque, oratorio, cantata or musical.
How was Jean-Philippe Rameau's relation with his librettists?
Unlike Jean-Baptiste Lully, who collaborated with Philippe Quinault on almost all his operas, Jean-Philippe Rameau rarely worked with the same librettist twice.

Question: Why didn't he work with the same librettists twice?
Self-contained rewrite: Why didn't Jean-Philippe Rameau work with the same librettists twice?