Where do Amazon product reviews live, and what can you get without signing in?
A logged-out visitor to an Amazon product page sees a small set of featured reviews Amazon chooses to surface — enough to get a sense of a product, not enough to analyze it. Amazon only pages beyond that featured sample for a signed-in session: click "See all reviews" as a logged-out visitor and you hit the same wall an API call without credentials would hit.
That's the shape of the problem the Amazon reviews API solves: it gives you a programmatic path to the same paginated review set a signed-in shopper can browse, returned as structured JSON instead of a page you'd have to scrape by hand.