In general, 30 years ago the concept of working long hours was something that was ordinary and part of the general business environment. There were periods of time where people were needed to put in extra long hours to get something done and if you were a salaried employee, it was a given that you would put in those hours to get the job done. If you didn’t put in the hours, you were not seen as a team player and it was unlikely that you would be getting promoted very fast unless your other contributions far outweighed your lack of extra effort. While there were periods of hard work though, it was generally understood that these would not last forever, that there would be periods of hard work and then there would be slack periods where no extra work was required and where in fact you could go home early. Thus the social contract with work was that while longer hours were required form time to time, on balance, there would be a period of shorter hours to compensate.
The concept of working longer hours has certainly survived the transition to a knowledge economy but the concept of compensatory shorter working hours has not made the transition. Not only has the working week been extended and the number of working hours increased but the ongoing pressure has not abated. There is no longer a slower time of year such as the summer where managers can breathe. This period is instead used to complete all of the projects that could not be completed during busier times. Work has shifted into periods such as the summer to compensate for times that it is just not possible to get everything done. As a result, there are no shorter hours anymore to make up for the longer hours required form time to time.