Fatigue doesn’t always look like fatigue. By mid-October, the change is hard to miss. The mornings are darker. The evenings arrive earlier. Temperatures are dropping. And for people working long shifts, rotating schedules or physically demanding jobs, seasonal changes can add another layer to something leaders should already be watching closely: fatigue. In field environments, we tend to think about fatigue as a safety issue—and it absolutely is. But it’s also a people issue.