If the journal is a rare or obscure publication, or if your citation was incomplete, it may take time for the request to be evaluated by the lending library. If the article is in a print journal, extra time is needed for staff to retrieve the issue and make the scan for you. Sometimes a library will discover that the article is in an issue that is missing, or issue might be too fragile to be scanned without damage. Then your request will move on to another library and the process will begin again.
ILL requests increase greatly in the weeks approaching midterms and finals during a semester, so response time may be slower due to the large number of requests. Please be aware of this, and request items as early as possible.
However, the most common reason for what seems to be a delivery delay is that the article was emailed by the system but it did not reach the patron’s in-box. Sometimes an email spam filter prevents the email from reaching their in-box. Sometimes patrons put an e-mail address on the ILL form for an account they don't check regularly. When requesting an article through Interlibrary Loan, give us the email address that you most commonly use.