Stance
Every email sent is a brand impression at effectively zero marginal cost. Unlike paid media you are not paying per view. Email also lands in a personal inbox rather than a feed, which puts it at a higher perceived level than most digital advertising.
The attribution trap
A subscriber who reads your emails is more likely to click a paid ad, search for your brand or convert organically. None of that shows up in email’s own attribution. Measuring email only on last click conversions undervalues it. Its true return includes the halo it creates across the whole marketing mix, which is also why the channel holds up better than its measured numbers suggest even as the inbox does more filtering and summarising. See attribution.
Caveat
The marginal cost framing has an asterisk in 2026. Sending to the dormant tail is no longer free, because the engagement drag is real.
A bad impression still has a cost
The reputational cost of a bad impression is real even when the send costs nothing. See engagement is the new deliverability.