Blemishing effect
A small negative alongside strong positives can make the overall message more persuasive.
Where it applies
Two of the eight page areas.
How to use it
Three ways to use it, and two to avoid.
- Show critical reviews rather than hiding them.
- Add honest “not right for you if...” copy after the main benefits, not before.
- Don’t chase a perfect 5.0, as purchase likelihood peaks at about 4.2 to 4.5 stars.
- Avoid: hiding or suppressing negative reviews, a banned practice under the DMCC Act 2024.
- Avoid: expecting it to work for serious flaws, where the effect was not shown.
What the research found
Shown in four studies under narrow conditions, with no independent replication found.
Purchase probability rose with rating to about 4.2 to 4.5 stars and then fell.
Shown in four studies, and only when people process with little effort and the minor negative follows the positives. No independent replication was found. Field data fit the idea: across three ecommerce sites, purchase probability rose with rating to about 4.2 to 4.5 stars and then fell.
Key research
Three sources, each checked.
Last reviewed
Ein-Gar, Shiv & Tormala (2012) When Blemishing Leads to Blossoming: The Positive Effect of Negative Information J. Consumer Research Read the source Maslowska, Malthouse & Bernritter (2017) Too good to be true: the role of online reviews' features in probability to buy International J. Advertising Read the source Eisend (2006)Meta-analysis Two-sided advertising: A meta-analysis International J. Research in Marketing Read the source
Before you use it · UK law
Hiding or suppressing negative reviews counts as publishing reviews in a misleading way, a banned practice under the DMCC Act 2024. The negative must be minor: the effect was not shown for serious flaws.
This is simply a pointer to check, not legal advice. Seek legal advice before you put this principle into action.