- I'm not sure if this is the primary point of the 100hr+ work-weeks. In my case, our submarine was going through an Engineering Refueling Overhaul in Norfolk so we were just incredibly busy.
100-hour work weeks not only save direct worker costs (you get 2.5x the labor at the cost of 1x), but also in managerial and other costs (you get 2.5x the labor for the cost of managing a 1x headcount).
But each individual is super proud of being able to give a 280% effort. It's just that after that long on the job, you are no longer capable of detecting when the math no longer adds up. And they are "high-spec" components--most people drop to 0% efficiency long before that 60th hour worked in a week. But there are no supermen in real life. Nobody on this planet can produce positive value in the 112th hour worked in a week, even if there are people out there willing to try, and also resilient enough to bounce back from it regularly.
It often boils down to the thoroughly debunked yet oft-echoed labor theory of value. In some people's minds, a person that works 60 hours in a week is 50% better than someone working 40. And if everyone in the organization works that hard, then the whole organization is that much better. The harder you bust your asses, the prouder you are of it, and the more you can ignore any objectively measurable outcomes.
In reality, this just gives the military completely unrealistic ideas about how actual productive labor happens, and how much it costs in time and money, and contractor businesses of the military-industrial complex gleefully take advantage of that.
And that is why a lot of my former shipmates got out after their initial enlistment and went into the contracting business.
If the whole system is being redlined when it's peacetime, then it only takes one thing going wrong, a single casualty, some damage to the ship, anything really to make the whole system collapse
There are a few people who do this, for whom "being awake" is basically the same as "working". Generally these few people are not employees, but part of the entrepreneurial world. However, they're outliers, and don't really counter your point.