Why does Dilbert's tie curl up like that?

I got my daily dose of Dilbert through RSS. It's from Tapestry Comics, where you can get feeds of other comics as well. Although sometimes I don't understand his joke, but when I do, I really like it very much. But there's one thing's been bothering me since the first time I saw him. Why does Dilbert's tie curl up like that? Googling the web gave me some answers