Purpose
This really can't be overstated. Proper name resolution is integral to successfully using PDQ Deploy and PDQ Inventory. If you manage your DNS server(s), it really helps to perform basic house cleaning like scavenging old records, consolidating or deleting old zones, etc.
Resolution
If you've seen errors such as Target Name Mismatch, Failed To Connect to ADMIN$, The Target Account Name Is Incorrect or other messages that basically state that a computer or target couldn't be reached then you may have a DNS issue.
The see also section below provides some good reading material on the subject.
See Also
Blog - DNS is A Four Letter Word
Blog - Healthy DNS Will Keep PDQ Inventory and PDQ Deploy Hummin' Along