If you poke around, you can easily find newly launched listing with hundreds of reviews ranking on the first page of popular keywords. E.g. search "earbuds". Th

If you poke around, you can easily find newly launched listing with hundreds of reviews ranking on the first page of popular keywords. E.g. search "earbuds". There will be a handful of results on the first page from no name brands, with all reviews within the last month, many unverified. That first page placement gets them thousands of sales before it falls off and they go launch a new product. I don't know the methods but it's more than just reviews.