Fatigue is such a killer of creativity and innovation. When I'm tired I feel my brain deliberately shying away from anything but the familiar and rote. How many great ideas have been sacrificed to stay an extra hour at work instead of using that hour for rest and replenishment?
It's a balance though, right? Sometimes I'm still tired at 6AM when I wake up and I have to get out of bed and do things anyway. Then other times I'm tired at 4PM and I just give up and go home. I think you've got to do the work, but being flexible around the margins is great.
