The image below shows a style of fence that I've seen frequently around train tracks. If you look closely, you will see that between the third and fifth horizontal wire from the top, the vertical wires have a kink in them where they run diagonally one way, then the other.
What is the function of this kink?
They're V-Mesh panels.
V-Mesh panel from Irish Wire.
The offset of the vee gives rigidity in the horizontal direction. The vertical rigidity is addressed by the fence posts. It's available in 2, 3 or 4 vee depending on the panel height.
Bending adds rigidity. Take a piece of paper, fold it, the bend gives it a rigid form to hold more weight. V-Mesh fences are also used in equestrianism as horse fencing helps keeps predators out and provides a safe, close fence spacing to prevent hooves and legs from getting caught
Just enough to provide some rigidity.
If that was not there then the fence panel would be very flexible.
