Keep a record of when and task was completed late. This can then be a measure of an individual for KPI purposes
When a task is late it will show as late but when the task has been completed there should be a filter for completed tasks and completed late. this makes it easier for managers to see who keeps completing work late.
Items that are completed but late should be in different column. Not just for individual tracking, but can point out if there are areas causing delays, etc. Otherwise, everything looks completed