When a campaign stops producing, almost everyone rewrites the copy first. Copy is the last thing to check, not the first — and working in the wrong order is how a two-day fix becomes a six-week one.
Here's the order I run.
1. Are you actually in the inbox?
Not your open rate. Open rates have been unreliable since Apple started pre-loading images, and a bot opening your email is indistinguishable from a person.
Send from a random sample of your domains to real Gmail, Outlook and Yahoo accounts you control. Look at where they land, with your own eyes. If you're in spam, nothing downstream matters and every other step is wasted effort.
2. Do SPF, DKIM and DMARC pass on every domain?
All three, passing, on every sending domain. Google and Microsoft made this mandatory for bulk senders in 2024.
Setting them is not the same as them working. I have seen DKIM silently fail on a third of a batch because of one copy-paste error in a DNS panel, on domains the dashboard reported as healthy.
3. How old are the domains?
Under 30 days and you launched too early, whatever the warmup tool said.
Domain age is a trust signal you cannot rush or fake. This is the constraint that sets your launch date — not when the copy is ready.
4. Did warmup actually run?
Twenty-one to thirty days, uninterrupted, three inboxes per domain at most. Pause it and the clock restarts.
And warmup score is not placement. That number tells you the tool is working. It does not tell you Google trusts you.
5. What is your bounce rate?
Above 2% and you have a data problem, not a messaging problem.
Bounces damage sender reputation faster than anything else on this list, and the damage compounds quietly. Verify addresses immediately before they enter a sequence, not once when the list was built — lists decay, and yesterday's valid address is today's bounce.
6. What is your sending volume per inbox?
Start at ten a day per inbox. Not fifty, not "the tool says 200."
Volume that ramps too fast looks like a spike to a filter, and a spike looks like a spammer.
7. Is your out-of-office rate above 2%?
This one isn't technical and almost nobody checks it. If a chunk of your replies are auto-responders, your buyers are not at their desks and the campaign is fine — the calendar isn't.
I learned this expensively: 5,000 emails into August, over 100 auto-replies, zero interested. The copy was good. I had launched into the quietest fortnight of the American business year.
8. Is the list right?
Pull twenty contacts at random and look at them yourself. Right title, right company size, right stage?
Most underperforming lists I audit are 30–40% wrong-fit. A third of the send was never going to reply regardless of what it said.
9. Now check the copy
If all eight of the above are clean and you're still getting nothing, fine — it's the message.
But that's the last stop, and you'll rarely reach it. Copy is the only part of this that feels creative, which is why it's the part everyone wants to fix. Infrastructure is boring, so it goes unchecked, and infrastructure is where almost every dead campaign actually dies.
The shortcut
If you want to check one thing before your next send, check placement in a real inbox. It takes ten minutes and it tells you whether the other eight matter yet.
I built a free cold email checker for the copy side of this — it flags the words and patterns that get a message filtered. It runs entirely in your browser and nothing is sent anywhere. But run the placement test first. The checker can only help once your email is actually arriving.