What is the main purpose of implementing miles-in-trail (MIT) restrictions?

The main purpose of implementing miles-in-trail (MIT) restrictions is to manage air traffic flow and prevent congestion in specific airspace areas or along particular routes, thereby maintaining safe separation between aircraft. Miles-in-trail is a traffic management procedure where aircraft are required to maintain a specified minimum distance, measured in nautical miles, behind the preceding aircraft on the same route. These restrictions are typically applied when the capacity of an airspace sector or a downstream fix is limited, often due to weather, equipment outages, ....