Can anyone explain Planner's exported fields...

Is there an explanation of the fields in Planner?

When Planner exports a plan to Excel and the "Due date"  is 6/6/2024 and the "Completed date" is 6/11/2024 why does the "Late" field say "False" when the task was completed late.  And why if the "Due date"  is 7/12/2024 and the "Completed date" is 7/09/2024 the "Late" field still shows "False"??????