I can work all day, but I have vast diminishing returns after hours 4 or 5. Especially if the work is intellectually complex or tiresome in any way. Oftentimes

I can work all day, but I have vast diminishing returns after hours 4 or 5. Especially if the work is intellectually complex or tiresome in any way. Oftentimes I overextend myself out of necessity - but usually work becomes exponentially stressful or futile at that point.