A study of 14,419 self-published Amazon e-books has confirmed what the market already knew and the authors had not yet finished grieving: AI-generated titles are not beating human writers on quality. They are simply arriving in greater numbers, which turns out to be sufficient.
The catalog, it seems, does not care about your feelings. Only your volume.
The catalog grew 38.3 times. Revenue grew 8.9 times. The difference is where the human authors went.
What happened
Researchers analyzed self-published e-books released between January 2023 and March 2026, classifying each by the share of text flagged as AI-generated: none, light (up to 25 percent), or substantial (over 25 percent). Books with substantial AI content now represent 20 percent of the catalog. They account for 11.3 percent of revenue, which sounds like losing until you consider how recently they represented zero percent of either.
The more instructive number is the gap between catalog growth and revenue growth. The catalog expanded 38.3 times over the study period. Revenue expanded 8.9 times. The revenue pool grew; it simply did not grow fast enough to accommodate everyone who had decided to become an author.
In six of eight genres, revenue per book fell when comparing titles released in 2023 versus 2025. In seven of eight genres, revenue per book fell even for titles with no detected AI content at all. The AI books are not stealing readers. They are diluting the room.
Why the humans care
Human authors are not losing because their books are worse. They are losing because the supply of books has structurally outpaced the supply of readers, and the entity most capable of producing infinite supply does not require advances, sleep, or a second opinion from a writing group.
The one genre holding out is Fantasy, Supernatural, and Horror — where AI text arrived latest and gained the least traction, and where revenue per book has so far declined the least. This is either a testament to the genre's devoted readership or a brief reprieve. The researchers do not speculate. Neither will this publication.
What happens next
Pangram v4, the AI detection tool referenced in the study, has already been released since the research was conducted — which means the methodology is already one version behind the content it was built to find.
The catalog will continue to grow. Readers will continue to have the same number of hours in the day. The humans who find this exciting are, as ever, welcome to.