Why do you write? What motivate you to be an author?
Welcome Jasmine!
I should think, as it is obvious, that many are only self-compelled to write. Which is fine, depending on the subject. Unfortunately that approach does not mix well with spiritual matters, leaving many to write as if inspired by God to speak for Him, as if sent. The byproduct of which is an atmosphere of presumed equal rights, equal to those actually chosen and sent. Apparently, many assume that all spiritual gifts are given to all people equally, muddying the spiritual waters intended to be pure and limited as given. The result of which is a broad way with no clear direction. These things are now evident in the great number of church denominations, and interpretations of the actually inspired Word from God.
Having said that, and my reason for doing so, is that my own answer to your question of what motivates me to write, is quite unique, biblical actually. Yet with so great a buzz of unauthorized free expression occurring, the still small voice of God is quite obscured.
My writing stems from a life appointed to goodness ending in disasters, leaving me unknowingly dead on God's doorstep crying out. To which He answered and caught me up in the spirit above the earth and into His presence, fulfilling things foretold. I was then returned with a task and an overflowing prevision leading to training, and eventually writing, for I could not and cannot contain it.