Which cold email subject lines should you avoid?

Avoid the ones modern filters and savvy buyers now recognise as cold-outreach clichés: "Quick question", "Quick chat", "Following up", "Touching base", "Circling back", "Re:" on a thread that never existed, "Are you the right person?", and anything with multiple exclamation marks or emojis.

These were effective in 2019; open rates on several have fallen by roughly 60% since 2021. They signal a template before the prospect reads a word of the body, which drags down the credibility of everything after.