Over the last 12 months, the Borks team sent just over one million cold emails on behalf of clients. Across dozens of verticals, every common offer shape, and a wide range of client sophistication. Running campaigns at that volume produces patterns that shorter horizons hide. The five lessons below are the ones that would save a new operator the most time if they had known them before sending email one.
None of what follows is clever. Most of it is the opposite of the advice that populates LinkedIn posts and agency landing pages. A million emails teaches you that cold outbound is a boring discipline and the operators who win are the ones least tempted to make it interesting.
Lesson 1: deliverability is simpler than the industry pretends
The consensus in cold email content says deliverability is an ongoing war requiring constant tuning, elaborate infrastructure rotations, and secret techniques. That is mostly a marketing pitch from people who sell infrastructure. In practice, deliverability is a small list of things to do and a smaller list of things to avoid. Once both lists are followed, deliverability holds steady for months without intervention.
The list of things that must be done
- Authentication. SPF, DKIM, and DMARC on every sending domain, aligned to the sending IP pool.
- Isolated sending domains. Never send from the primary corporate domain.
- 14-day warm-up. No new domain sends a campaign without a 14-day ramp of real conversational volume.
- Volume discipline. 30 sends per inbox per day as the ceiling. Most operators who break this rule lose their domain inside 14 days.
- Clean verification. Two-pass verification plus Scrubby on catch-alls, every time.
The list of things not to do
- Do not track open rates. The tracking pixel alone cuts placement by 20 to 40 percent.
- Do not send links or attachments on the first message.
- Do not use HTML signatures with images or complex formatting.
- Do not send from private infrastructure providers without a specific reason. Most are weaker than Google Workspace on reputation.
- Do not rotate through elaborate IP pools. It is complexity for no gain.
Our current setup across 10,000 client inboxes is the simplest possible. Porkbun for domains, one verified reseller for Google Workspace inboxes, our private sequencer, a single corporate credit card, and a bi-weekly inbox placement test. That is the entire deliverability stack. Average inbox placement across the portfolio sits at 95 percent.
Lesson 2: volume is not a strategy
Every founder eventually considers doubling their send volume when results plateau. Nine times out of ten, doubling volume makes results worse. A campaign running at 0.4 percent reply rate and 20,000 sends per month does not become a better campaign at 40,000 sends. It becomes the same bad campaign burning twice the infrastructure.
Volume only pays when the underlying rates are competitive. Above 2 percent positive reply rate, adding volume compounds revenue. Below 1 percent, adding volume accelerates domain burn and signals to mailbox filters that the sending operation is a spam cannon. The right move below 1 percent is always to fix the list or the copy first, then scale.
Scale-ready reply rate
> 2.0% positive
Fix-first threshold
< 1.0% positive
Volume where most campaigns break
40K+ / mo without discipline
Lesson 3: the list matters more than the copy
If you have to choose, always fix the list before you fix the copy. A great email to the wrong person bounces. A mediocre email to the right person books. The ratio of contribution to total reply rate runs about 70 percent list quality, 30 percent copy. Most operators have the priority inverted and spend six weeks rewriting copy on a list that should have been rebuilt.
The most common list mistakes
- Broad industry targeting. 'Technology' as a category captures buyers who have nothing in common.
- No sub-vertical segmentation. A fintech buyer is not an edtech buyer. Same copy on a combined list dilutes both.
- No event-based enrichment. Static lists lack urgency. Signal-driven lists have a reason to reply this week.
- Reused lists across campaigns. A list burned on a prior campaign is poison for the next one. Always de-duplicate against previous sends.
Lesson 4: the agency model punishes breadth
Agencies that serve every vertical look appealing on paper because every dollar counts. In practice they produce worse results for every client. Vertical specialisation compounds. The second client in a vertical is 2x faster to onboard than the first. The fifth is 5x faster. The playbooks, the list sources, the copy angles, the objections, all reuse. An agency serving 10 clients across 10 different verticals has 10 campaigns that share nothing. An agency serving 10 clients in two verticals has five playbooks and half the operator hours.
For clients picking an agency, this means a narrow-vertical agency almost always beats a broad-vertical generalist. The narrow agency has seen every objection, knows the exact copy angles that convert, and has a list of buyers who have already been warmed on previous campaigns. Breadth is a marketing move, not a performance one.
Lesson 5: the boring operators outperform the clever ones
The single most predictive variable across campaigns is operator discipline. The clients who ask for special copy tricks, custom infrastructure, exotic verticals, or novel signal stacks underperform the clients who do the basics well. The boring campaign runs the same four-step sequence with tight list segmentation, consistent volume, and standard reporting. It outperforms creative campaigns by 20 to 40 percent on reply rate and 50 percent on retention.
If you are starting a cold email program, run the boring version first. Standard list, standard warm-up, standard sequence, standard volume, standard reporting. Get it to 2 percent positive reply rate. Then consider whether any clever addition actually improves on the baseline. In most cases, it does not. The discipline of not breaking a working system is the single biggest edge in cold email.
One million emails teaches you that the winning operators are boring, consistent, and invisible. They do not post clever content about deliverability because they do not have the interesting story. They have the boring story of campaigns that book meetings every week because the fundamentals are followed without deviation. That is the game.