How do you measure the success of an infographic in terms of viewer engagement and information retention?

A few metrics that I would consider to measure the success of an infographic:

In terms of viewer engagement:

• A high click-through rate (CTR): High CTR happens when the overall design is eye-catching.
• Viewer's Time spent on the Infographic: The longer people view it, the more engaged they are with it.
• Shares on social media: People love to share valuable content; more shares mean more value an infographic provides.

In terms of Information retention:

• Follow-up actions: Whether viewers take the call to action (CTA),  eg. making a purchase, signing up for a service, or contacting a business after seeing the infographic.
• Long-term value: Infographics with a clear visual message should stay in viewers' minds for years and build brand value over the long term.