What DMARC Protects You From, and What It Does Not

DMARC is a narrow authentication protocol that verifies whether the visible "From" address in an email is authorized through SPF or DKIM alignment, but it is not a spam filter, phishing filter, or general trust signal as many teams mistakenly believe. Organizations deploying DMARC at strict enforcement levels (p=reject) while thinking it makes them "phishing-proof" may neglect other essential security controls that address threats DMARC doesn't cover.