Smart woman. She knew that her own boredom with her chapters would soon translate into boring writing. Right now, it might just be an overactive Inner Critic. Soon, her blahs would indeed translate to the page.
We toggle between two pivots as we write a book. When things are clicking along, the writing going well, it's easy to fall into complacency. A kind of satisfaction or contentment. Like in life, too much of that becomes boredom.