Everyone has a book that only he/she can write

Rav Tzadok (Machshovos Charutz #15): Even though there are already many seforim in the world and Shlomo cautioned against making an unlimited amount of seforim (Koheles 12:12), nevertheless every accomplished student has something new to teach which is uniquely his and that no one else is able to discover… Not a day goes by without a new insight from some accomplished student of that generation. Furthermore that particular insight, which is part of the process of sustaining the existence of the world, needs to remain fixed and permanent in the world. There are in this matter many additional factors and processes concerned with preserving and perpetuating this new insight.