I'm always curious to what extent work hours correlate with productivity. I think it was patio11 who shared his story of a salaryman co-worker fixing his bike in his cubicle on a Saturday he was "working" in the office.
And while I haven't seen first-hand the Japanese style overwork, I have seen Silicon Valley startup "overwork" up close and have similar concerns. My pet theory is that in early-stage startups it's so unclear what is actually valuable and productive work that the overwork becomes a proxy for productivity.
The issue is that most startups are in survival mode and hence has a natural pressure from that. The trick is to manage expectation at IC level. Knowing that there is this natural pressure commit to only what you can deliver in 15hrs/week. Then work "hard" and overdeliver equivalent of 30hrs/week. Spend 10hrs on above the weed activity (evaluate, measure, communicate, course correct etc.). Be religious about this template.
Overworking East Asians end up spending a lot of time completely zonked out at their desks, scooting the mouse cursor back and forth over the same spreadsheet or Word doc until it's time to go home
Tokyo Sonata is a pretty good fictional movie about the honor associated with working. Some salarymen would fake a job, leaving each day in a suit. On the other side of the spectrum, there are people forced into quitting because they would go to work and sit in a room all day since management didn't want the dishonor of firing someone. It definitely comes across as odd to a foreigner.
And while I haven't seen first-hand the Japanese style overwork, I have seen Silicon Valley startup "overwork" up close and have similar concerns. My pet theory is that in early-stage startups it's so unclear what is actually valuable and productive work that the overwork becomes a proxy for productivity.