This function lets your administrator or designated person know if your flight is proceeding as scheduled. For example, even though your itinerary says you should be landing at JFK at 15:22, the system will know if you’re likely to arrive early or late, and update your itinerary accordingly.
In addition, it shows your administrator the actual location, on a map, of your flight. This doesn’t add new information, but it can be fun to watch the pretty pictures of where all your people are.