A delegation of authority may be needed when the scope or complexity of an incident is greater than what is covered by the current official’s existing authorities.
Correct statement
The accurate statement (as seen in ICS/incident management questions) is: a delegation of authority is needed when the incident scope is complex or beyond existing authorities.
Why this is the reason
In such situations, higher-level officials must formally delegate authority so the Incident Commander or responsible official has the legal and organizational power to manage the larger or more complex incident. This does not remove ultimate responsibility from the granting authority, but it ensures the person in charge has sufficient authority to act.