Th flat profile of a box clasp maintains the continuous visual flow of a strand necklace or bracelet at the closure point. Lobster clasps, on the other hand, introduce a protruding element that interrupts that flow.
Stone Story
Ruby and sapphire are both corundum, with color being their only distinction. Red earns the name ruby, and every other direction the color goes falls within the sapphire family.
Made With Purpose
If one clasp fails, you lose the piece. If two independent closure points fail simultaneously, you lose the piece. The second scenario is orders of magnitude less likely, which is the entire case for dual-security construction. For significant fine jewelry, the figure 8 is not optional. The stakes make the argument.