Why the crease in these handlebars?

Just curious if these creases serve a purpose or is it just some general design?

Image: https://cimg4.ibsrv.net/gimg/bikeforums.net-vbulletin/2000x1504/20190112_135628_c9e1e3f3a836bdfe788e224c67be88714eca035c.jpg Image:...