Heraclitus, Greek philosopher, 500 BC, knew a little something about the future of communications and email, with his maxim “You never step into the same river, as new waters flow on to you.”  Nothing truer given the unending flow of messages that cascade through our inboxes today.

So, when it comes to an email campaign, or pitching a reporter, does one surmise that if they didn’t reply, then they never saw it?  That your missive continued on, out of your target’s active window, pushed deeper and further away as if perhaps it never existed.  Or that the no response was the deliberate response?  Perhaps in the torrent of messages, while distracted by other thoughts, they only focused on those emails whose sender’s name rang familiar, or took action on the subject lines that addressed their immediate concerns.

Do you dare send the email again, unchanged?

Advertising conventions say it takes at least 7 repetitions to make an impression.

But then you’d be considered a certified spammer, blacklisted by their server.

Or do you tinker? Perhaps changing the subject line and trying again?

For PR practitioners and marketers concerned with divining how to reach and get a reply, Marketing Sherpa cites a recently published a study citing a double-send strategy, with the subject line changed for non-respondents. In their case study, a non-profit boosted donations 55%.  Their summary…

It happens all the time. A person goes through their inbox, reads a subject line and deletes the message. Had the subject line been different, would the person have opened, clicked and converted?

See how one nonprofit garnered 55 percent more donations by sending an email twice -- first to all subscribers, and then with a new subject line to subscribers who did not open. Check out the results metrics from both messages.

MailChimp, the email marketing company (free email campaigns up to a limit) also has a Study of Best and Worst Open Rates based on subject lines.   While a provocative headline would seem to be more enticing and effective, their stats show the fairly mundane headers with telling vs selling -- Acme Spring Newsletter vs Best Ideas for Spring Savings – being far more effective in being opened.