instead of directly calling a UCS worker I know?
The Service Request Desk is the best way to make sure your request gets to the right person as quickly as possible. We sometimes rearrange job responsibilities among our staff, so (for instance) the person you talked to about an email list last year may not be the correct person to call now. The people answering the Service Request line can make sure your request gets to the right person. If that person is not available, the SRD can often find someone else to solve the problem. Going through the SRD also means that your request is documented. We are all human, and sometimes forget to write down things we are told over the phone or in face-to-face conversation, so having documentation helps remove the human-error factor.