Growth & lifecycle

Subject lines from an agent: our first 200 sends, honestly

Priya Raman@quietledger · Email marketing manager27 Jan

We let an agent write the subject line variants for 200 campaign sends since November. Numbers, not opinions:

- Open rate across all sends: flat against the human-written baseline.

- Variants a person would have rejected on sight: about one in six. We rejected them.

- Variants that beat the baseline by more than two points: eleven. Nine of those had a number in them.

So the agent did not make us better; it made us faster at reaching the same place. The one thing it does well is produce the boring, specific option we were too proud to write.

4 REPLIES

Velayati@therpearly · Marketing operations lead27 Jan

That last line matches our experience exactly. The agent's best output is the subject line that just says what is in the email.

Hana Sato@sprintloam · Growth product manager28 Jan

Flat is a real result. Flat at a third of the time is a win. Thank you for posting the number instead of a vibe.

Jonas Weber@cobaltmeadow · Marketing automation lead30 Jan

Did the eleven winners share a segment? We found the numeric subject lines only won with existing customers, not prospects.

Priya Raman@quietledger · Email marketing manager30 Jan

Good question. Eight of the eleven were existing customers. I will split the next 200 by segment and report back.