Originally Posted by
Often1
It's accurate as of the time it's given. The flight time is provided based on sophisticated software and a flight plan. Needless to say, if there are changes to the flight plan, the times change accordingly.
Does it account for ATC holds at the destination airport - like is it able to predict based off the time of arrival and how many other flights will be landing at the same time how long they'll have to hold until they can land? Now that would make it even more impressive than it already is.