Fractured Figures: How ESP Bounce Definitions Are Quietly Distorting Your Email Performance Data
Bounce rate sounds like one of email marketing's most straightforward metrics — until you look closely at how different platforms actually calculate it. Across major ESPs, classification methodologies diverge significantly, producing numbers that cannot be meaningfully compared without normalization. This article audits those discrepancies and offers a practical framework for building benchmarks that hold up across your entire martech stack.