Or terrible at writing emails, or configuring high volume sends, so that they don't look spammy.
I work for a market research company. Most of our projects gain survey responses via market research panels - or panel marketplaces - so we don't need to email people to ask them to fill in surveys. But we do plenty of projects for clients who send us mailing lists of their customers, who we then contact to fill out surveys.
This is all fine and good but when you're contacting completely different lists of people all the time it's really easy to end up looking like a spammer (this is also why platforms like Sendgrid, and Mailchimp - although great in many ways - aren't a good fit for a market research use case: you're not just contacting the same list, or subsets of that list, over and over; mostly you're contacting different lists for each project, unless you're following up for a single client).
We've had to build our own mailing platform to do this successfully, so that our email is actually delivered into peoples' inboxes, rather than going to their spam folders.
And it's not just the content of the email that matters: it's how you send it, making sure you have DKIM and whathaveyou configured correctly, whether the HTML is valid, etc. Our system automatically checks every aspect of an email before anyone is allowed to hit send (and each send has to be reviewed by one of a list of approved individuals). It also checks the mailing list and cleans out any addresses that are likely to be bad, or who have unsubscribed. Again, if you're not careful about who you send email to, you'll look like a spammer.
A big chunk of our business depends on our ability to get emails into inboxes, so we take great care to make sure that happens. Reputation is everything when it comes to bulk emailing in market research. Because humans under pressure to deliver sometimes cut corners we've baked that great care right into our systems. They're not foolproof, but it's now really quite hard, and would require concerted and deliverate effort, for anyone on our team to send an email without the vast majority of intended recipients receiving it.
This whole thing is a kind of nightmarish arms race but I've been doing this for long enough that I'd put money on it not being Microsoft's spam classification doing it wrong here.
- notice IP is blacklisted, so the email doesn't even end in spam
Great engineering. Users must be excited MS allows them to send e-mail to servers they know are blacklisted, so will not be able to receive the reply from.
Great [honest] engineering would be to just refuse to send the e-mail and tell the user that they are not allowed (by MS) to communicate with this recipient.
One of the signals they use for classifying spam is people clicking "Report Message->Junk" in Outlook, so it's probably a constant battle with people who forget they signed up for something and call it junk.
People forget they signed up for something, didn't opt-out, got on some list from a conference they attended, etc. and just report as Spam even though there's an unsubscribe link.
Frankly, the vast bulk of the email in my Spam folder isn't egregious fake medicine and the like. It's mostly low quality mailing lists, much of which isn't much different from what ends up in my inbox.
> didn't opt-out, got on some list from a conference they attended
I would totally consider emails I received because of either of those things as spam. If I get an unsolicited email, it gets reported as spam regardless of the presence of an opt-out link. I wouldn't click any link in an email that came from someone I didn't opt into getting email from.
If they were, they'd still be bleeding users like they did when Gmail came on the scene. That's why I switched; Hotmail 20 years ago did not appear to do any kind of spam blocking at all.
Today, Outlook.com and Hotmail.com combined still have a pretty strong market share.
Does it really or does it just mean that nobody cared enough to do it for whatever reason?