Why does the Dyson hair straightener have a line?

Maybe it’s Dyson’s springboard design.

The Dyson hair straightener uses Dyson's patented flexible elastic plate design, which wraps mechanically to control and gather hair. This new technology is difficult to understand. My understanding is that it can bend the metal plate according to the curvature of your hair to better fit your hair. It can also cause minimal damage to the hair.