I mean people don’t usually even do 8 hours of deep focus.

Also some things just have wall time. Sometimes it may take 3-4 hours to roll things out and test. Babysit some dashboards, cicd.

Working “12” hours may mean you get 3-4 attempts/iterations at something rather than 2-3. Over time that may add up.

It could also mean 6 hours of meetings followed by another 3-5 hours of coding + breaks

These aren’t deep focus, but they still take time.

I guess mostly agreeing you. My experience of working 10-12 hours is you are less efficient but you can get more done.

It’s rarely worth doing for long periods of time. But in some situations it can push things forward.