The stopwatch says one thing, but I can see in her shoulders she is carrying something heavier than a slow lap. Years ago I would have just logged the time and moved on. Now I trust what my eyes and my gut tell me as much as the sheet, and I coach the person standing in front of me.
More people experience this than they realize.
You have learned to weigh what you see in a person as much as what the data says.
If this sounds familiar, the Library can help you find the bigger picture.