Email marketing success largely hinges on deliverability. DNS logs are essential because they provide insights into how your domain is being resolved. This is crucial for email deliverability since issues in DNS resolution can lead to emails being marked as spam or not delivered at all. By regularly monitoring DNS logs, you can identify and rectify issues such as DNS misconfigurations, SPF (Sender Policy Framework) failures, and DKIM (DomainKeys Identified Mail) misalignments.