Tracking key metrics like open rates measures subject line effectiveness, while click-through rates (CTR) indicate content engagement. Conversion rates assess how well emails drive actions like purchases or sign-ups.

Optimizing send times ensures emails reach subscribers when they're most likely to engage, while balancing frequency prevents overwhelming audiences. Improvements based on data include refining subject lines, adjusting layouts, or enhancing calls-to-action. Continuous A/B testing and analysis strengthen campaign performance, ensuring better engagement and results over time.