[finolex1]

How do you decide how much to work in a week, or when to stop working each day?

Personally, it feels like having unstructured work hours leads to an implicit competition between everyone to do the most work humanly possible, and any leisure hours begin to feel almost sinful.

[mreome]

Goals. You work with management to define what needs to be done by when, then set your schedule to maximize your personal productivity to meet those goals. You generally can't really have that kind of flexible schedule without organized/effective management. But it can be a win for Management because the idea is that each employee is maximizing their own productivity, potentially letting the employee have more free time (while still meeting goals) which makes them happier, more well rested, and thus even more productive. In the long-term your more productive employee will get more done.

[tachyonbeam]

I guess I was lucky because in my field I was able to do well without overworking myself. I enjoyed my project and how much I worked was based on how motivated I was. I did leisure activities when I felt the need to. I know people who are grad students in deep learning though, and it really seems way more competitive than what I'm used to.