Sean Glaze uses the backpack metaphor to argue that leaders should be curious about what their team members are carrying outside work. Before assuming someone's underperforming, ask what's actually going on in their life.
Do you know what's in their backpack? Just like kids on their way to school, every person on your team is carrying something with them that is affecting their mindset and attitude and interactions and performance. Have you checked in or asked about what they might be dealing with outside work, or have you made negative assumptions about their behaviors? When you're curious, when you seek to learn about what it is your people are carrying with them, you become far less judgmental about how they carry it, and you become far more impressed at what they can do having had that extra weight attached. Instead of judging people and making negative assumptions about why their performance might be different, perhaps you could be more curious and ask questions to understand what might be in their backpack. That's what effective leaders do.
