Most of what you have been taught about email is mechanical.

Right message, right person, right time. Send on a Tuesday at ten. Keep the subject line under fifty characters. Cut anybody who has not opened in ninety days. Test the button colour. Segment more.

Almost none of it concerns the human being on the other end, which is a strange gap given that the human being on the other end decides everything. Nobody explains what a person is doing when they open their inbox, how attention gets allocated in the half second your name appears, why some copy persuades and some bounces off, or what your emails are teaching people to feel about you over the course of a year.

So we have ended up with an industry full of tactics floating free of any explanation of why they might work, which is why the tactics keep failing and nobody can say why. We have all been taught email wrong, and the fix is not a better list of rules.

What follows is where I part company with the standard advice, and more importantly why, because the reasoning matters more than the positions.

The frame

I do not believe in best practice but I DO believe in guiding principles.

Best practice is a phrase that smuggles in an assumption, which is that there exists one correct way to do this and it works everywhere. For a channel where outcomes depend on who your audience is, how they arrived, what you promised them, what you sell and how often they need it, that assumption falls apart almost immediately.

What exists instead is a small set of things you would simply not do, a set of principles that point you in the right direction without dictating the execution, and then an enormous space where the only honourable answer is to test it on your own audience and find out.

The short list of things you would not do

• Buy, rent, scrape or borrow a list.

• Hide, bury or complicate the unsubscribe.

• Manufacture urgency that is not real.

• Send to your whole database because the date says you should.

• Promise one thing at signup and deliver another.

Five things, and they are not best practice, they are closer to the rules of the road. Everything on that list damages you in every context, for every audience, in every industry, which is what makes it different from advice.

The principles, which are directional rather than prescriptive

• Prove who you are. Authentication, consistent identity, a sender name people recognise.

• Send to people who asked, and keep asking whether they still want it. Permission is a state, not a one-off event.

• Give more than you ask. Across the whole programme, measured rather than assumed.

• Understand before you optimise. Foundations first, because optimisation assumes the system already works.

• Respect the inbox. You are a guest in a space somebody else is trying to manage.

Notice that none of those tells you when to send, how long to write, how often to mail or what to put in a subject line. Principles survive contact with a different context; prescriptions break the moment your situation stops matching the one the advice was written for.

Benchmarks

The reason you want a benchmark is not a marketing reason

I do not believe in benchmarks, and I have said so often enough that people occasionally get cross about it. Before the argument, though, some sympathy, because the wanting is completely understandable and it is not a professional failing.

Festinger set out social comparison theory in 1954, describing how people evaluate their own opinions and abilities by comparing themselves with others, and crucially that we lean on social comparison most heavily when no objective standard is available.

Which describes email reporting exactly. There is no objective standard telling you whether a 22% open rate is good, so the pull toward finding somebody else's number to sit next to is not laziness, it is how humans handle uncertainty. We are built to want the validation, and sitting with a number you cannot judge is uncomfortable in a way that has very little to do with marketing.

The answer is still no.

Why the number will not help you

• It is an average of businesses that share nothing but a send button. A daily deals list and a quarterly B2B newsletter are in the same dataset, which produces a figure describing nobody.

• The published figures contradict each other anyway. Go looking for an average unsubscribe rate and you will find numbers that differ by nearly six times, all published confidently.

• You cannot see how it was built. Which senders, which industries, which definition of the metric, which period. Without that, the number is a rumour with a decimal point.

• It answers a question you were not really asking. You wanted to know whether to worry. A benchmark cannot tell you that, because worry depends on your trend, not somebody else's average.

Metrics

What the internet measures, and what I look at

Worth clearing up a thing people get wrong about my position on opens, because I am not anti-open-rate.

Opens are a useful indicator. They tell you something directional about whether your audience is warming or cooling, they are worth watching as a trend, and I do look at them. What they are not is a success metric, and the distinction between an indicator and a success metric is the whole argument.

An indicator hints that something might be happening. A success metric tells you whether the thing you were trying to achieve happened. Privacy protections and image pre-fetching mean an open can fire without any human ever looking, so building a decision on opens alone is building on sand, and reporting them as your headline number tells your business almost nothing about whether email is working.

The deliverability metrics that matter

View the deliverability metrics here

The point being that these are separate from your marketing metrics and they should be reported separately, because they are answering a different question. Marketing metrics ask whether the email worked. Deliverability metrics ask whether anybody had the chance to find out.

And on the marketing side

• Click-to-delivered rather than click-to-open. Action against what was sent, which is the right denominator.

• Reply rate. The least gameable engagement signal you have, and the one most programmes never look at.

• Revenue or pipeline per thousand sent. Which stops anybody arguing that a bigger list is automatically a better one.

• Engaged list size, by cohort. The figure that tracks revenue, rather than the one that goes up when you add people.

• Complaint and unsubscribe rates as trend lines, split by email type. Compared only against previous versions of that same email.

There is a longer version of all of this in my metrics and reporting guide, which goes through each one properly.

The missing half

Nobody teaches you the human, which is why the advice keeps failing

Go and read the first ten results for any email marketing question. You will get mechanics. Timing, frequency, segmentation, subject line length, template width, the right message to the right person at the right time.

What you will almost never get is an explanation of the person receiving it.

Nobody tells you that the inbox is a task environment rather than a browsing one, so people are triaging rather than evaluating, and the question they are asking is not whether your email is any good but whether it needs them. Nobody explains that recognition is processed before content, which makes your sender name do more work than your subject line ever will. Nobody mentions that repetition builds familiarity and erodes attention at the same time, from the same input, which is why sending more can make you both better known and less noticed.

Nobody explains that every email is a pairing event, quietly teaching people what your name means, so that after a year your brand carries whatever feeling it has been arriving with. Nobody explains why the same offer converts when it is framed as a loss and stalls when it is framed as a gain. And almost nobody connects any of it to deliverability, despite the fact that mailbox providers are reading human behaviour and turning it into placement decisions.

So the advice fails, and it fails in a specific way. Somebody follows the prescription correctly, sees no improvement, and concludes that email does not work for their business. What has really happened is that they were handed advice about the machine when their problem was the human.

Which is the narrative I am trying to push, and the reason there is now a whole run of psychology-led work in the Vault: inbox psychology, copywriting psychology, brand associations, journey design using TFDS. Not because psychology is fashionable, but because it is the missing half of an education that most email marketers were never given, and it produces better results than the tactics it replaces.

Side by side

Where I part company with the standard advice

With the framing above in mind, the specifics. Treat the right-hand column as my position and my reasoning, not as a new set of rules to follow without thinking.

Sending and frequency

The internet says: The best time to send is Tuesday at ten in the morning.
What I say: Send time optimisation is close to the bottom of the list of things that affect your results, and any universal answer is describing somebody else's audience. Test it on yours, then stop thinking about it and go and fix something that matters.

The internet says: Be first in the inbox in the morning.
What I say: A load of nonsense. You are competing with a filtering system and a human triage habit, not with the other senders' timestamps.

The internet says: Send more to earn more.
What I say: Frequency without consequence accelerates the process by which people stop noticing you. Email is an impact channel before it is a performance one, and volume is the lever people pull because it is the one they can pull without permission.

The internet says: Sending less is the safe option.
What I say: Under-sending is a deliverability problem too. Long silences followed by a big send look like a compromised account, and memory decays in the gap.

The internet says: Email everybody at Black Friday, it is the one week that justifies it.
What I say: Going wide at peak is the single most expensive thing you can do to a sender reputation, at the exact moment it is under the heaviest load.

Your list

The internet says: Cut anybody who has not opened in ninety days.
What I say: Ninety days is a round number that got repeated until it sounded like a finding. Engagement is a risk question, not a date, and the right window depends on your buying cycle, your seasonality and what meaningful action looks like outside the email.

The internet says: Unsubscribes are a loss to be minimised.
What I say: An unsubscribe is a good outcome and a spam complaint is a bad one. Make leaving easy, because you are choosing between two exits and only one of them damages you.

The internet says: Clean your list to fix your deliverability.
What I say: Cleaning treats the symptom. How people got onto your list is the strongest predictor of how your email performs, so the problem is nearly always upstream in acquisition.

The internet says: They opted in, so you can email them.
What I say: Somebody who ticked a box to get ten percent off did not sign up for a relationship. Consequential and intentional opt-ins need completely different treatment and most programmes treat them identically.

The internet says: A bigger list is a better list.
What I say: Gross growth is a vanity metric. Engaged list size is the number that tracks revenue, and a smaller healthier list frequently earns more than the bloated one it replaced.

The internet says: Run a re-engagement campaign to win them back.
What I say: Most of the time you should not. The growth you are looking for is usually being blocked upstream rather than hiding in the dead part of the database.

Copy and tactics

The internet says: Personalisation means using their first name.
What I say: A name in a subject line changes what somebody is called. Real personalisation changes what they need to know, based on what they did, bought or asked for.

The internet says: Create urgency to drive action.
What I say: Only when the urgency is real and only late, when somebody already knows what they would get. Applied early it trains your audience to wait for the last chance email, because they learn that is when the real offer appears.

The internet says: Test your subject lines.
What I say: By all means, once the things that carry most of your result are sorted. Most email effort goes into the rounding error while the twenty percent that moves the needle sits untouched.

The internet says: Build a welcome series.
What I say: Build an orientation flow. The job of the first few emails is not to convert somebody who just arrived, it is to establish what your name is going to mean for the next two years.

The internet says: Use AI to write your emails at scale.
What I say: Engagement decays on heavily automated copy, and declining engagement is what pushes you into spam. The filters are not detecting AI, humans are recognising the patterns and disengaging.

Tools and advice

The internet says: Your platform has a deliverability score, so use it.
What I say: Your ESP is a product, not an advisor. Several platforms present metrics labelled deliverability that are not deliverability metrics in any meaningful sense, and a number that moves while your placement does something else is worse than no number at all.

The internet says: A 99% delivered rate means your email arrived.
What I say: Delivered means the receiving server accepted it. It says nothing about whether a human had the chance to see it, and the gap between those two things is where most disappointment lives.

The internet says: Keep spam complaints under 0.3%.
What I say: That is a ceiling, not a target. Treating it as a goal is like treating the speed limit as a minimum. Work to under 0.05%.

The internet says: Buy a warm-up tool to fix your placement.
What I say: Filters are getting too good at spotting the patterns those tools create. Warming your reputation is something you do through behaviour over time, and there is no product that substitutes for it (they can help though if you pick the right one!! It ALL depends).

The internet says: Scale your cold outreach.
What I say: Cold email is dying and will be finished before the end of the decade. The shift required is to build something people come to, with a smaller audience of much higher quality.

The internet says: Deliverability is a technical job for somebody else.
What I say: Deliverability is the ongoing health of your sending reputation, shaped by your behaviour over time. Behaviour is a marketing decision, which makes it your job whether or not you wanted it.

How to tell good email advice from bad

Which is the part that matters most, because you should not swap one set of borrowed rules for another set of borrowed rules, including mine. Six questions to run anything through, including this post.

1. Does the person giving the advice also sell the thing it recommends? Not disqualifying, and worth knowing. A platform explaining why you need to send more is describing its own business model.

2. Is it testable against your own data? Advice you cannot check is a belief. Advice you can check is a hypothesis, and hypotheses are useful.

3. Does it come with conditions, or is it universal? Anybody who tells you the right answer without asking about your audience, your acquisition or your cycle is selling a prescription.

4. Does it explain the mechanism, or only the tactic? A tactic with no explanation cannot be adapted when your situation changes, which it will.

5. Does it ask you to do more, or to do less? Most real improvement in email comes from subtraction, and most bad advice comes from addition, because addition is easier to sell.

6. Would it still be true if your audience were completely different? If yes, it might be a principle. If no, it was always context wearing a lab coat.

The conclusion

None of this is an argument that everyone else is wrong and I am right. Plenty of what works for one brand will do nothing for another, which is precisely the point, and the fair position is that context beats best practice every single time.

What I would ask instead is that you stop looking for the rule and start looking for the reason. Learn what your audience does in an inbox, what your emails are teaching them to feel, and how the mailbox providers read all of it. Once you have that, most of the advice you find online becomes easy to sort, because you can see whether the mechanism underneath it applies to you.

And if you take nothing else, take this. Respect the inbox, stop asking so much of your audience, and start giving. Almost everything I believe about email is downstream of those three things.