Passive income through book royalties allows you to earn money without actively working for it. Once your book is published, you can sit back and watch the royalties roll in, even if you're not doing anything. This can provide a significant amount of financial stability, as you can earn money from your book for years after it's been published. Book royalties give one a feeling of creative fulfillment. Earning royalties from a book can be a rewarding experience and show that all the effort that went into writing it was worthwhile. Writing a book can also help you establish yourself as a subject-matter authority, which may open up further chances in the future.