My black ranger garb, i.e. pieces I made with scraps and pieced together. I was dumb and forgot to bring my archer's brace and elf ears to this shoot. Thankfully my dear friend had a pair of spare ears!
I could answer this. For a ranger is important to be fast, light and unnoticed by anyone. So, that's actually the main reason. The reason is, because that's the hand taking the arrows from her back, and it's important to be as fast as it could, and one shoulder or sleeve could cost the ranger's life.