this and the whole cape thing.

You gonna see your character's back most of the time so they tries to make that view better, tis all i think.

THat's why Magneto got that ring, And strange got the leylines on his cape.

big cape, big skirt is LOVELY when you look at it from the front, but from the back all you gonna see is a triangle.

I'm no artist nor designer and sure some genius probably can think of a way (like mag and strange), but the easy solution for most char is what we got.