User blog:Sanjithechief/Why allways the left side?

I noticed that many characters have some mark on the left side! For example: Shanks,Luffy. Zoro, Garp have a scar on their left eye. Shanks and Jozu lost a left arm. Dragon has a tatto on his left side. There are more examples, but the question is why the left side? Did Oda do this for fun, or is it easyer for him to draw this things on the left side?