After years of letting vendors give away free or discounted products in exchange for reviews, Amazon has finally banned the controversial practice, which ruins the effectiveness of its ratings.

In one example, demonstrated by review analyzer ReviewMeta.com, an umbrella with a 4.7-star rating and over 100 reviews had only four legitimate reviews that averaged 2.7 stars.

In a statement, Amazon VP of Customer Experience Chee Chew noted progress in devaluing the weights of reviews that weren’t “verified purchases.” Direct action against review manipulation is being taken. Still, the company took a stricter stance against buying stars, which is detailed in updated community guidelines.

The new guidelines, which appear to be written with the consumer in mind, prohibit incentivized reviews with the sole exception of the Amazon Vine and books, which still allows reviewers to obtain pre-publication copies. The Vine program, to the uninitiated, is an invitation-only network of “trusted” reviewers that can receive new and pre-order products for free, which help ensure that no Amazon products are without feedback. According to its rules, vendors can’t and don’t have to make contact with the reviewers—Amazon is the middleman.

Amazon changing its mind represents a massive victory for the consumer, given how popular these reviews are. It’s hard to quantify the stakes, but according to one study, more people begin a search for products on Amazon, not Google. Since Consumer Reports and The Sweethome don’t show up in those search results, all those people are left with is the stars to guide them. And as anyone who has been lost with a drained phone can tell you, the stars are a poor substitute for actual guidance.

The number of incentivized reviews out there has been pegged at 20%, according to ReviewMeta’s calculations, but that figure alone may not be meaningful. In some cases, 100% of a product’s reviews are incentivized, and in other cases the number will be very low, as Consumerist noted.

With so many reviews already out there influenced by free or discounted product, will Amazon scrub its system of influenced reviews?

The company did not respond to queries by publication time, but that infamous umbrella still has 107 reviews and a 4.7 star rating.

Ethan Wolff-Mann is a writer at Yahoo Finance focusing on consumerism, tech, and personal finance. Follow him on Twitter @ewolffmann.

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