thing,
That is one of the biggest problems I've seen in the military. "Leaders" who believe that the only metric worth judging their subordinates by is time spent in the office!
The guys still working on plans or staff work at 1800 are often, in my experience, not very good at time management. But if you're very good at what you do and finish everything asked of you by 1500, it looks bad if you knock off early.
Flexible working has been an enormous success for some companies, but we're still in the stone age by judging people on how long they sit at their desks, not what they're doing while they're sat there.