I don't care this much about maximizing output for my company, period. I've been careful to avoid more Hill and SF-type take-over-your-life jobs, because I get a lot out of my flexible time (writing a book, offering hospitality to others, seeing theatre, building things) that I would not get out of a job and that are difficult to trade money for.
Of course it's eminently reasonable for you (or anyone) not to care that much about maximizing output for their employer. However, employers might care about maximizing output, and if it turns out that long working hours (which are surely not optimal for the employees) aren't even good for the employers then that's pretty interesting, no?
And if that turned out to be true, and enough employers were convinced of it, then the range of options available to employees who don't want to work very long hours might increase a lot, which would also be interesting.
Conventional wisdom, and many studies, hold that 40 hours of work per week are the optimum before exhaustion starts dragging your productivity down too much to be worth it. I read elsewhere that the optimum is even lower for creative work, namely 35 hours per week, though the sources I found don't all seem to agree.
In contrast, many tech companies in silicon valley demand (or 'encourage', which is the same thing in practice) much higher work times. 70 or 80 hours per week are sometimes treated as normal.
How can this be?
Are these companies simply wrong and are actually hurting themselves by overextending their human resources? Or does the 40-hour week have exceptions?
How high is the variance in how much time people can work? If only outliers are hired by such companies, that would explain the discrepancy. Another possibility is that this 40 hour limit simply does not apply if you are really into your work and 'in the flow'. However, as far as I understand it, the problem is a question of concentration, not motivation, so that doesn't make sense.
There are many articles on the internet arguing for both sides, but I find it hard to find ones that actually address these questions instead of just parroting the same generalized responses every time: Proponents of the 40 hour week cite studies that do not consider special cases, only averages (at least as far as I could find). Proponents of the 80 hour week claim that low work weeks are only for wage slaves without motivation, which reeks of bias and completely ignores that one's own subjective estimate of one's performance is not necessarily representative of one's actual performance.
Do you know of any studies that address these issues?