About 25 years ago I was brought in on contract to teach a course on networking to a group of people sent there on a job skills training thing.

Many of them wanted to be there, some didn't. And so the first thing I was told was to look for people whose faced looked green: They were inn in front of computers, and this was the Windows '95 days, and they all had Solitaire, and if I saw a green glow it meant someone had zoned out and was playing Solitaire.

Over the years it turns out a lot of managers takes pretty much that approach to managing employees. Instead of talking to people and paying attention to whether they are productive, they've gotten comfortable with looking for superficial signs of whether or not people appear to be productive.

And the first sign they used to look far was whether or not you were even at your desk typing...

Of course managers who have spent their career dependent on that as their sign you're working will freak out when they can't see you.