Hiring a Troubleshooter might be the best money you ever spent. What you don’t see you don’t know, might not even imagine.
Many time employees know the Manger’s schedule; even when the Manager doesn’t think s/he has a schedule.
For example; Mrs. Peters arrived at work every day at 9 am it took her ten minutes to sort herself, and then she would do a walk of the premises, then go to the bathroom. She spent about fifteen minutes in the bathroom.
When she came out, she would do another walk, then go into her office and was not seen on the floor until the afternoon.
She didn’t know this was her schedule, but the workers did, and could time their movements and actions.