The "Run Script" action in Flow Designer is specifically designed for situations where custom scripts need to be executed. This functionality allows users to write and run their own JavaScript code within the flow, providing flexibility to perform complex tasks or calculations that go beyond the capabilities of standard actions.
Utilizing this action is particularly beneficial when the default actions available in Flow Designer do not meet the specific requirements of a process. For instance, if a user needs to manipulate data in a way that's unique to their application or environment, the "Run Script" action gives them the ability to accomplish that through custom scripting.
It also is vital in scenarios that require dynamic decision-making or when integrating with other systems where straightforward predefined actions in ServiceNow may not suffice. Thus, when the need arises to implement logic or functionality that cannot be achieved with built-in features, the "Run Script" action becomes the ideal solution.