Because like I tell my daughter, by now we should know our right from our left:

• Right: اليَمين (al-yamīn), which comes from the same root as the country Yemen (اليَمَن), which archaically means “south” (reflecting a time when the compass was oriented to the east and the rising sun, putting south on the right)
  
• Left: اليَسار (al-yasār)