1. Sending from a name your list doesn't recognize
"MTJE Team" or "no-reply" doesn't build recognition the way a real name does. Inboxes reward familiarity — "Henry from MTJE" gets opened by people who remember who Henry is, especially on mobile where the sender name shows before anything else.
2. Writing the subject line last, in a rush
The subject line is the whole pitch. If you write the body first and slap a subject on at the end, it usually just restates the first line of the email instead of giving someone a reason to open it. Write two or three options and pick the one that would make you stop scrolling.
3. Vague subject lines that promise nothing specific
"Quick update" and "Don't miss this" tell the reader nothing. Compare that to "3 subject lines that got us 40% opens last month" — the second one earns curiosity because it's specific. Specificity is what separates a real subject line from filler.
4. Ignoring preview text
Most people never touch this field, so their email client fills it with "View this email in your browser" — a wasted second sentence that could have been doing work. Preview text is a second subject line. Use it.
5. Sending on a schedule only you understand
Twice a week for a month, then silence for six weeks, then three emails in one week because you have news — that pattern confuses the algorithm and the subscriber. Inbox providers read erratic sending as a signal something's off, and deliverability quietly suffers before you notice.
6. Treating every subscriber like the same person
A subscriber who joined yesterday and one who's been on your list for two years should not get an identical email. Basic segmentation — new vs. returning, engaged vs. gone quiet, buyer vs. browser — is the difference between a message that feels relevant and one that feels like noise.
7. Never removing people who've stopped opening
It feels wrong to shrink your list on purpose, but mailbox providers track engagement per sender. A list full of people who haven't opened anything in six months drags your reputation down for everyone else on it, including the people who do want to hear from you.
8. Burying the one thing you actually want read
If an email has three calls to action, a long story, and a P.S. with the real news, most readers won't get to the part that matters. Decide what the single goal of the email is before you write a word of it.
9. Copy-pasting subject lines that worked for someone else
A formula that worked for a SaaS newsletter in the US won't automatically work for a Nigerian ecommerce brand's list. Borrow the structure, not the words — test what your specific audience actually responds to instead of assuming.
10. Never looking at the data after you hit send
Open rate, click rate, and unsubscribe rate are telling you something every single time. The marketers who improve fastest are the ones who actually read those numbers and change one thing at a time, instead of sending the same way for a year and wondering why nothing moves.