A retail brand is running a static ad campaign on Pinterest with the goal of increasing website traffic. The media planner wants to determine which ad group is performing most effectively in driving users to the site. Which metric should the media planner prioritize for comparing ad performance?

For a campaign focused on increasing website traffic, Click-through rate (CTR) directly measures how often users click on the ad to visit the site, indicating ad effectiveness in generating interest. Cost per click (CPC) shows the efficiency of those clicks, revealing how much is spent for each user driven to the website. Together, these metrics provide a clear picture of both performance and cost-efficiency in achieving the traffic goal. Conversion rate (CVR) and cost per acquisition (CPA) are more relevant for sales or lead generation goals, not solely traffic. Impressions and cost per mille (CPM) measure ad visibility and cost per thousand views, but don't indicate user action towards the website. Pin clicks and engagement rate are broader engagement metrics and don't specifically track clicks to the external website.