For most people on the ground, power wires are no big deal. For landscape photographers, they are annoyingly visible in almsot any photograph you want to take. (That’s why Photoshop’s clone tool was invented.) Looking up, the wires are easily seen against the blue sky. The problem for glider pilots is the wires are invisible against the background of foliage and it’s always the wire you don’t see that’s going to kill you.
Take a look at this photo, taken in a semi-rural area near Mendoza, Argentina. You can see lots of wires, right? Can you see the street lamp that’s illuminated during the day? The wires going to the lamp? The wires near the lamp?