Urgent changes represent an unrecognized and unmanaged cost to the typical organization. The costs are easily measured in terms of unplanned downtime, utilization of IT resources, and lost business opportunity. Part of the reason is that many individuals use urgent changes as a means of working outside the established change management process. This leads to unmanaged and unmeasured changes, resulting in unplanned downtime.
For this reason, ITIL stresses the need to have a well defined urgent change process in place that is flexible enough and fast enough to be followed in urgent situations, yet formal enough to meet all the needs of an effective change management process. This enables the change manager to increase the scope and effectiveness of change management.
Often, people use urgent changes as a method to avoid detailed change/release testing. The suggested ITIL process says that even if implemented with minimal or no testing, every change should go through full regression testing even if it is done after the implementation.
Organizations that do this often find problems with urgent changes after they have been installed but before they negatively impact the business. This enables the organization to resolve the problems before negative impact occurs. Another benefit of the urgent change process is that it ensures the change is logged and tracked so that the organization can measure the impact of the urgent changes it implements.