If a marketer can double the quantity of product reviews for a brand, their sales will increase on average by +35%. But if they double the ad spend, sales will typically increase by just +10%.

This core truth about the power of consumer influence comes from an extensive review by the Marketing Science Institute.

The broader concept points to an immediate path for better brand ROIs if it is properly understood and acted upon.

For instance, what is intriguing about how influencers impact the brand purchasing funnel is that their effect is not equal across all elements of the funnel — influencers more powerfully impact mid- to lower-funnel metrics such as “consideration” and “preference,” but generally fail to move Awareness.

Read more on MediaPost.