The market is saturated with crap that doesn’t sell under its own merits. In theory a review signals that not only did that product sell, but somebody actually cared enough to leave a review.
An online market is especially tricky for consumers because you can’t really look at the product to judge it for yourself. You have to make do with a product description, specifications, or photos. All of which might be incomplete, poorly translated, or photoshopped / AI-generated.
So reviews tell you what other people thought. It’s their first line of marketing after SEO (Search Engine Optimization). Of course, unethical companies are out there using paid and fake reviews, so it’s not like a savvy shopper can even use the reviews to judge quality.
Anyway, as someone else said, don’t engage with these emails. You’ll just end up with more emails if you do.
It’s a common turn of phrase that people use when explaining something to someone who seems unclear on a subject.
I hope this clears things up.