It's not fair

In the delivery space, stuff comes in cycles. We’re currently in a cycle where people are unhappy with spam filters. There are two reasons they’re unhappy: false positives and false negatives.
False positives are emails that the user doesn’t think is spam but goes into the bulk folder anyway.
Fales negatives are emails that the user does thing is spam but is delivered to the inbox.
I’ve sat on multiple calls over the course of my career, with clients and potential clients, where the question I cannot answer comes up. “Why do I still get spam?”
I have a lot of thoughts about this question and what it means for a discussion, how it should be answered and what the next steps are. But it’s important to understand that I, and most of my deliverability colleagues, hate this question. Yet we get it all the time. ISPs get it, too.
A big part of the answer is because spammers spend inordinate amounts of time and money trying to figure out how to break filters. In fact, back in 2006 the FTC fined a company almost a million dollars for using deceptive techniques to try and get into filters. One of the things this company did would be to have folks manually create emails to test filters. Once they found a piece of text that would get into the inbox, they’d spam until the filters caught up. Then, they’d start testing content again to see what would get past the filters. Repeat.
This wasn’t some fly by night company. They had beautiful offices in San Francisco with conference rooms overlooking Treasure Island. They were profitable. They were spammers. Of course, not long after the FTC fined them, they filed bankruptcy and disappeared.
Other spammers create and cultivate vast networks of IP addresses and domains to be used in snowshoeing operations. Still other spammers create criminal acts to hijack reputation of legitimate senders to make it to the inbox.
Why do you still get spam? That’s a bit like asking why people speed or run red lights. You still get spam because spammers invest a lot of money and time into sending you spam. They’re OK with only a small percentage of emails getting through filters, they’ll just make it up in volume.
Spam still exists because spammers still exist.