Which metric is a critical factor in determining ad position along with the bid?

The metric that plays a crucial role in determining ad position, alongside the bid, is Quality Score. Quality Score is a comprehensive metric that assesses various aspects of your ads, keywords, and landing pages. It evaluates the relevance of your ads to the search queries, the expected click-through rate (CTR), and the landing page experience.

A higher Quality Score indicates that Google considers your ad to be more relevant to users, which can lead to a better ad position at a lower cost per click. This means that even if your bid isn't the highest, a strong Quality Score can enhance your ad's visibility and improve its ranking on the search results page.

While impressions, click-through rate, and ad relevance are important components of an ad's performance, they do not directly influence ad position the way Quality Score does in conjunction with the bid. Impressions measure how often your ad is displayed, click-through rate relates to how frequently people click on the ad when they see it, and ad relevance assesses how well your ad matches the intent behind user searches, but Quality Score encapsulates all these aspects to determine overall effectiveness and positioning within the ad auction.