Which metrics matter most to your business?

My business is promoting myself as a dark fantasy romance author through my social media platforms, newsletter, blog, and author website. To determine successful content there will be several factors I can use to measure across the various platforms. For my webpage and blog, key word tracking, and referral traffic will matter. For my social media platforms will factor in reach, impressions and engagement. The larger audience I can reach and the more engagement I can encourage the more successful my content. My newsletter, blog, and emails will require my attention to gaining subscribers. All these different ways of tracking the success of the content aligns with the platform type as well as how my target audiene view my specific content type.