Chapter 3 · Retention 03
The Retention Problem

Subscribers don't churn — they fade.

100% 75% 50% 25% 96% 48% M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11 M12 Months after subscribing

Measured as share of cohort opening at least one email per month

This is the Substack 2023 design system, applied by Curio Design — a design-style library for AI agents. Full Substack 2023 guide → designbycurio.com/learn/substack-2023