Some negative reviews are good for you

An espresso machine was perceived as 16% better when positive reviews were accompanied by a negative but mostly irrelevant review

Previous tip: ‘Friend’ influencers drive more sales than ‘opinion-leaders’ (All tips here)

Tip type: Existing research (August 2016)

Negative reviews that are mostly irrelevant are good for business

Impacted metrics: Customer acquisition
Channels: Reviews


If you have mostly great online reviews, don’t try to hide all your negative reviews. A few negative reviews will boost your sales.

The caveat is that they should be irrelevant comments in the eyes of most readers (e.g. a 1-star review because an e-book isn’t available in print).


  • When positively reviewed products also have a negative but irrelevant review, people judge the product as better. It works with different rating systems (stars, thumbs up/down, recommend/don’t recommend).

  • For example, experiment participants rated:

    • An espresso machine with four 5-star reviews 16% higher when it included a fifth irrelevant 1-star review saying “there is a considerable difference in taste when mineral or filtered water are used rather than tap water” compared to when it didn’t.

    • A camera 12% better when it included an irrelevant 1-star review (alongside 4 positive reviews) compared to when the same irrelevant review gave it 5-stars.

  • The effect is weaker if the irrelevant reviewer is someone the reader knows.

  • Negative reviews that are relevant only for a subset of customers have the same effect, except for those affected.

  • If the negative review(s) is highly relevant to the product, then this effect doesn’t apply. Prioritize fixing your product instead.

Why it works

  • We are skeptical by nature. Negative irrelevant reviews (there isn’t anything actually wrong with the product, for our purposes) give us the confidence that our positive information about the product is complete, so more likely to be true.


  • It’s unclear how many negative irrelevant reviews are best. However, if there are relatively many, the general rating will be lower and people may simply glance over your product without bothering to read reviews. The researchers mostly tested only one negative review with four positive reviews.

  • The products used in the experiments were highly rated on average (4.5 stars). It’s not clear (but likely) if this works for products with lower ratings.

Companies using this

  • Most companies either try to suppress negative reviews (sometimes aggressively) or take a hands-off approach (but still usually respond to them).

  • Few or no companies appear to deploy irrelevant negative reviews tactically.

Steps to implement

  • Assuming you have good-to-excellent reviews for your product, don’t try to hide a few negative reviews that have little or no relevance to your core product’s benefits.

  • You may even want to display a few irrelevant negative reviews prominently on your website (e.g. “This is what our product doesn’t give you: [show 1-2 irrelevant negative reviews]”).

Study type

Lab and online experiments, Israel and English-speaking countries


Shoham, M., Moldovan, S., & Steinhart, Y. (August 2016). Positively useless: Irrelevant negative information enhances positive impressions. Journal of consumer psychology, 27(2), 147-159.

[Link to paper]


Israel Institute of Technology, The Open University of Israel, and Tel Aviv University, Israel

Remember: This research could be disproven in the future (although this is rare). It also may not be generalizable to your situation. If it’s a risky change, always test it on a small scale before rolling it out widely.

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