It is often considered that if a person works longer hours, he produces higher value. However, that may not be true. In the early 1900s Ford Motor made some experiments with increased working hours to figure out whether working extra brings extra value.They found out the golden mean is 40 hours per week and if the hours are more than 40 per week and go up to 60 hours per week, there is a minor increase in productivity that lasts only three to four weeks and then it turns negative.
At the end, the long hours result in a work that must be redone or produced lower quality value.
It is even observed that people who work too many hours for long time, at some point get personal problems that affect both their life and their work quality.
Defendants of long work weeks tend to point as examples countries like Thailand, Pakistan or Korea where it is normal to work more than 40 hours per week and point this as their advantage compared for example to European countries.
The facts say something else. In sex of the top ten most competitive countries in the world for 2012 (Sweden, Finland, Germany, Netherlands, Denmark, and the United Kingdom) it is illegal to demand more than 48-hour work week. So in this countries it is impossible to see legally a work week that lasts 50, 60 or even 70 hours per week – something that is quite common in some parts of the United States. Among the top ten countries for the years up to 2016 there have always been 5 or 6 countries that prove shorter working weeks to be good enough.
As a conclusion, people should not feel guilty and should not apologize if they leave work at 5:30 pm. If they work longer than that continuously, at some point their productivity will decrease and at the end it will be bad for the company as the total value produced will be less.