Tests that the DMARC policy is enabled and not in testing mode.
When implementing a DMARC policy, a website may wish test the policy before allowing email recipients to obey the rules. This is done by setting a policy to "none". This means that no action will be taken for bad emails, except for reporting them according to the DMARC record. Once there is confidence that the DMARC policy will not block legitimate emails, this policy should be upgraded to "quarantine" or preferably "reject".
If the policy is "quarantine", then emails that do not pass the requirements will likely end up in the spam folder. With a policy of "reject", the bad emails will not be delivered at all.