What Does Amazon Know About Your Thanksgiving Groceries?

For a business that started as an online bookstore and grew into one of the largest companies in the world, the Amazon of 2020 would feel, to an Amazon customer in 1999, at least a little bit familiar.

An ancient firm by internet standards, Amazon has grown like a medieval city, still defined by its distinctive old center but made a true megalopolis by vast sprawl. It has modernized substantially, but its basic features are still intact — and being used well beyond their imagined limits.

Take Amazon’s review system. Some of the site’s most prolific reviewers have been rating products on the same five-star scale for more than 20 years, and occasionally, their messages from the distant past surface on product pages. A customer browsing books about sailing might encounter a review written by Jeff Bezos himself in 2001, recommending one title as “intense and disciplined.” (Thirty-four people have found this review “helpful” since then.)

In the 1990s, Amazon reviews were both functional and, as a concept, anti-establishment: What if anyone could be a book reviewer? Then: What if anyone could do what Consumer Reports does? Then: What if anyone could review pretty much anything, for any reason at all?

The rating system has adapted to encompass reviews of shoes, cosmetics, athletic gear, medical equipment, TV shows, software, musical instruments and furniture. A more recent undertaking, however, is proving difficult: What can an Amazon review tell us about fresh food?

“Taste like an onion, did the job,” reads one recent review of a piece of produce. Another went further: “Tastes good.”

Not everyone reviewing Amazon’s “Yellow Onion (Brands May Vary)” gave it five stars, however. Ninety customers have rated the Yellow Onion as deserving just one. “They went bad too fast,” one reviewer warned. “Moldy and decaying, rotten outer layers,” another wrote.

Between satisfaction and disappointment, we find more nuanced takes on the onion. A reviewer who gave her onion four stars described it only as “Muy grande.”

Amazon reviews are deceptively challenging texts. Successful products often fall between four and five stars, which means consumers must also take into account how many reviews there are, how they’re distributed and what qualities are taken into account by reviewers.

Reviews of a movie tend toward attempts at criticism, while reviews of a budget USB battery usually focus on whether or not its size and charging abilities match the listing. Reviews that demand slightly more description — a shirt, for example — produce a range of subjective judgments and descriptions (“soft” or “boxy”) that a buyer can parse, alongside clues about what a reviewer values. As winter approaches, review sections for price-inflated propane patio heaters, many from brands that didn’t exist on Amazon a few months ago, are concerned with one question: Will this thing actually ship in the estimated time? If it doesn’t, will the company answer my calls?

Lots of Amazon review sections are filled with complaints about order fulfillment and customer service. Others are full of robotically positive reviews, leaving readers to guess, based on writing cues, which are actually real.

Amazon is constantly intervening to maintain a review system that is, if not exactly healthy or even fair, at least usable. Separately, though, years of trying to extract useful information from Amazon product listings have made customers more skillful in the form, as readers and reviewers. Onion reviews, however, defy some of these expectations.

“These might be the last frontier of authentic reviews,” said Saoud Khalifah, the chief executive of Fakespot, a company that analyzes e-commerce reviews. His tools suggest that produce reviews are of “very high” quality, meaning that they’re likely written by real onion customers about authentic onion experiences.

Mr. Khalifah provided a few theories about why this might be the case. Most of Amazon’s produce sells directly through Amazon or Amazon-owned Whole Foods, meaning there are no third-party sellers jockeying for placement in search results who might be motivated to play dirty and seed fake reviews. There are no brands, either — just single listings for produce types. He compared it to Amazon’s early days, when fake reviews were relatively rare.

Authentic as they may be, the onion reviews are still confounding. Reached using a gray-market tool for acquiring Amazon reviewers’ contact information, reviewers for yams, yellow onions, lemons, garlic, salt and ginger did not respond to requests for comment.

A reviewer named LoLinda, who declined to share her surname, did not recall writing a review for russet potatoes. (“Divine,” she wrote, leaving five stars. “Believe it or not, not all potatoes are created equally. I’m a potato connoisseur and these are delicious!!!”)

“I seriously doubt anyone scrolls down to read potato reviews when buying,” LoLinda, 45, said. She posted hers only to clear the potatoes from her “Review Your Purchases” section. (I’m a neat freak and love to see things through to completion,” she said.)

An onion reviewer responded too. “I vaguely remember leaving the onion review,” said Katt Winter, 38. “I bet it was red onions and around 2017.” (It was April of that year. “Super tasty red onions. They make everything better. They are full of flavor and hold up well in the fridge crisper. Definitely recommend to onion fans,” she wrote.)