The other day, while doing my usual niche research on Amazon, I saw something that made me pause:

A sponsored KDP book ranking on the first page — with only one review… and it was a 1-star.

Ouch.

I couldn’t help but think: the publisher must have a big heart (or deep pockets) to spend money promoting a product with such poor social proof.

Running Ads on a Poorly Rated Book Is a Costly Mistake

In my opinion, this is one of the biggest mistakes you can make when running Amazon ads for your books.

Here’s what I’ve learned after running ads on many KDP books over the years:

Amazon ads work best when your product (book) is already solid — ideally with a 4-star rating or higher.

Personally, I avoid running ads on any book that has an average rating below 4 stars.

Why? Because poor ratings hurt both your CTR (Click-Through Rate) and CR (Conversion Rate).

A book with no reviews might still get sales through ads — especially if the cover, title, and niche are appealing.

But a book with negative reviews (even just one)? It’s almost guaranteed to lose money.

Think about it:

• Most people won’t even click on your ad when they see that 1-star rating.
• If someone does click through, they’re unlikely to buy once they see a bad review on the product page.

Now here’s the tricky part…

Even if your book is genuinely good, a single negative review can make it look bad to potential buyers. Especially, if the book lacks positive reviews!

What to Do Instead (Smart Ad Strategy)

Don’t waste ad spend on books with only negative reviews.

Aim for an average rating of 4 stars or higher for better CTR and conversions.

If you want to get the most out of your KDP ads, here’s what I recommend (and personally follow):

• Create a high-quality book — this is non-negotiable.
• Optimize your book description to clearly show the benefits for the reader.
• Add A+ Content — use images and bullet points to highlight value and build trust.
• Price your book competitively. Sometimes, pricing it $1–$2 higher than the average can increase its perceived value and improve ROI.

This is exactly what I do to promote my books with Amazon ads — and it works.

Conclusion: Let the Product Do the Heavy Lifting

Amazon ads are not a magic fix — they amplify what already exists.

If your book has a strong foundation (quality content, good reviews, optimized listing), ads can accelerate your results.

But if you’re promoting a book with negative ratings, you’re likely just speeding up how fast you lose money.

So before you launch any campaign, ask yourself:

👉 Is my book ready to be advertised?
👉 Would I buy this if I saw it as a sponsored product?

If the honest answer is “no,” focus on improving the book first — then let your ads do the work.

This is the approach I use for every single KDP book I promote, and it consistently brings me better results, lower ad spend, and higher ROI.

Talk soon,

Subha

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