I have a SharePoint 2010 OOB list workflow that usually takes less than minute to complete. However, I found a list item where the workflow begun 30 minutes after the start time, but less than a minute to complete after it did start. For example, the workflow was initiated at 3:30 pm in the history list. However, it started running at 4:00 and finished at 4:00 pm. The list only has around 300 items. What can cause this?