What are myths that no longer apply (e.g., keyword stuffing)?
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Some email advice has a surprisingly long shelf life. And some of it went stale years ago but keeps getting passed around like it's still gospel. If you've ever avoided the word "free" in a subject line out of pure habit, this one's for you.
Here are the myths that don't hold up anymore, and what actually replaced them.
"Avoid trigger words like 'free' and 'buy now'"
This was real advice in the early 2000s when filters were basically keyword lists. Those days are gone. Modern spam filters weigh context, sender reputation, and engagement signals. A well-authenticated sender with good engagement history can write "free shipping" all day. An unknown sender with no reputation gets flagged regardless of word choice. Write naturally.
"Image-only emails dodge text scanning"
The idea was that images carry no text for filters to analyze. It never really worked, and it definitely doesn't now. Filters flag image-heavy emails as suspicious on structure alone. They also run optical character recognition on images to extract text. On top of that, image-only emails fail on accessibility and don't render for subscribers who have images turned off. It's a triple loss.
"White text on a white background hides keywords"
This one felt clever circa 2003. You'd stuff invisible keywords to trick filters while readers saw a clean design. Filters have scanned for hidden text for a long time now. Finding it doesn't just neutralize the trick. It actively marks your email as deceptive, which is worse than the original problem.
"Send at the right time to slip past filters"
Timing your send to hit inboxes at 6 AM on a Tuesday doesn't affect how filters evaluate your email. Filters don't care what time it is. They're checking authentication, sender reputation, content signals, and how your past emails performed. Arrival time doesn't factor in.
The thing all these myths have in common is they treated filtering as a puzzle to outsmart. Modern filtering isn't a puzzle. It's a reputation system. What actually moves the needle is consistent authentication, low complaint rates, good list hygiene, and content your subscribers genuinely want to open.
But if you're not sure what's helping or hurting your deliverability right now, our SOS hotline is free and genuinely helpful (no sales pitch).
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