They think the culture expects them to be busy continuously

A non-stop working culture is generally less productive. A more productive approach is to allow people to follow their own body rhythms where possible. People vary, but for the most part they can concentrate for no more than 90 minutes before needing 10-15 minutes to consolidate memory and rest the brain. They may not realise this, though, and workplace culture often forces staff into spending more and more time working less and less efficiently.