For email deliverability, domain authentication and server configuration account for only 20% of the equation. The remaining 80% is split between email security (50%) and regulatory compliance (30%).

If a company doesn’t adhere to regulations, just to name a few: CAN-SPAM, CASL, CPRA, PCI DSS, Google/Yahoo - authentication alone won't suffice.

When a company faces email threats and bad actors distribute phishing emails through its servers, email authentication won't bring much sense to email deliverability.

In the email industry today, without robust email security measures, almost anyone can read your emails, alter their content, fake SSL/TLS certificates, or even redirect inbound email traffic to compromised servers. When this occurs, authenticated domains alone won't ensure your emails reach the inbox.

So while domain authentication is critical, it becomes ineffective if there are cybersecurity vulnerabilities on the server or if email industry regulations are neglected.