And then you have guys like a co-worker that I have, who is known for staying at this 9-5 job until 2am sometimes: most of the time that I walk by his cube, he's reading Facebook/doing some other shit that's not related to work.
yeah. this happens too. it is just the fact that you can not relate hours into productivity. it might be really productive and passion employee, or might be un-socialize-able slacker who just decided to slack at office instead of doing same thing at home. Once you get married this might go away, so if you know that person is married AND staying late - it probably have higher probability that (s)he is working and not slacking.
