Return on ad spend (ROAS) has long been the default metric for evaluating marketing performance. It’s simple, immediate, and easy to communicate: dollars in versus dollars out. But simplicity can be misleading.

As the digital ecosystem becomes more complex and organizations demand clearer accountability for growth, ROAS alone is no longer sufficient. Performance marketing is evolving from a narrow focus on efficiency to a broader mandate: driving meaningful, long-term business outcomes.

ROAS tells you what’s working now, but not necessarily what’s working best or forecast further performance. High-ROAS campaigns often capture existing demand, such as retargeting users already close to conversion.…