This article shows how to connect acquisition, conversion, and retention...

https://touch-wiki.win/index.php/How_to_Decide_Whether_to_Pull_Back_on_a_Channel_That_Looks_Good_on_Paper

This article shows how to connect acquisition, conversion, and retention instead of treating each channel alone. Track CAC, AOV, and repeat purchase rate together, and weigh tools like $199/month plans against the sales and customer value they support.