There may be secondary and tertiary goals, but each email you send should have a primary goal.

https://medium.com/@rezzz/is-an-email-campaign-a-success-2534345266f4

Is an email campaign a success? - Jason Resnick - Medium

Analyzing campaigns (or sequences) is probably the most boring, but critical step, in your email marketing that you can do. Even if you aren’t a seasoned email marketer, you must analyze your emails…

Medium