Assess the marketing spend return by comparing your customer acquisition cost (CAC) to your customer lifetime value (CLV).
Values of 1:1 or lower (i.e. 1:2) are considered to be wasting resources., while higher values (i.e. 2:1) express a balanced marketing strategy. One has to take care and not take this value to higher than 3:1, since higher values may imply underinvestment in marketing, which could harm future growth.
This comparison is critical for assessing the return on marketing investment (ROMI or ROIM).