In this episode of Always Be Testing, host Tye DeGrange sits down with Kayla Castro, Senior Manager of Affiliates & Partnerships at Zenni Optical, to talk about the evolving world of affiliate marketing. Kayla shares her experience leading affiliate programs and offers practical insights on how to audit and optimize affiliate strategies for long-term success.

The conversation covers common mistakes brands make in affiliate marketing and why internal communication is critical for gaining leadership buy-in. Kayla also dives into the complexities of measurement, breaking down MTA, MMM, incrementality, and attribution models in a way that helps marketers understand how to use the right tool for the right decision.

They explore how to balance efficiency, partner diversity, and sustainable growth while leveraging AI as a supportive tool without losing the human touch that drives authentic, trust-based relationships with partners. Beyond marketing, Kayla shares personal perspectives on travel, books, and professional growth, making the discussion both practical and relatable.