One of the (many) advantages of having a longer beard or moustache is that of styling. Men with close cropped beads have no oppotunity for variation short of shaving and then they are caught within that particular style until the follicles grow back out.
But a man with longer bears can move the hairs this way or that to elicit a particular effect. I give you Frederick III, at this time in 1870 the crown prince of Prussia and later to serve as Emperor of the Holy Roman Empire. Many of the paintings and photographs that I have seen of his royal majesty present him with a somewhat conventional beard. I have seen others where the beard is somewhat split in the middle, slightly less conventional but nothing too dramatic.
But here, he has taken the comb from the center of the chin and drawn it horizontally, in some ways extending the horizontal pull of the moustache down across the chin.
It may perhaps have been effected for a practical purpose of revealing the medal at his throat rather than having it concealed by a vertically combed beard.
I like to think it was more than that.