Major symbolism starts with the point, and examines where and how it travels, to derive an understanding of the personality. This travel is not restricted to strokes. It can be equally applied to white space within a page, or the page as a whole.
This looks at the stroke structures, or sequence of stroke structures, reflecting upon what they are symbols of.
Within this context, a strong leftward moving stroke through a signature would be symbolic of removing one's self from life. How that removal is manifest, depends upon what else is in the handwriting.