Loop for a reason that nobody has mentioned yet. When you clip directly onto the string and draw, the "string pinch" causes the knock to come partially off the string. I was at full draw a couple of times and my arrow actually fell off the string. Thank god I didn't dry fire it! On a short ATA bow without a loop, if you draw and let down your arrow will very likely fall off the string. With a loop, I can draw and let down all day and the arrow stays tight on the string.That is THE reason I put on a loop.