Somebody not actually working at work could be due to many different factors. Yes one could be that they are lazy and half-assing their job, but it also could be that they just aren't motivated. Maybe they don't feel connected with their job. Ideally, an employee is motivated to to a good job for reasons other than its a daily grind and its what they have to do.

The HR industry terms this "Employee Engagement." If I had to guess, Fog Creek has quite a few "disengaged" employees.