There are changes that a system admin can make that are not logged in the Audit Log. These include configuration changes to system-level settings like changing date and time format. Without seeing who made the change, organizations have difficulty tracking admin activity for potential security risks.

 
These settings include but are not limited to:

• jira.date.picker.java.format
• jira.date.picker.javascript.format
• jira.date.time.picker.java.format
• jira.date.time.picker.javascript.format
• jira.projectkey.pattern