I like rings on a worm. I’m not sure if there’s a ton of scientific evidence to back up my preference here, but it seems like a lot of the best worms and my personal favorites have rings around them. So these rings must feel more realistic to a fish and that causes them to hold onto a bait a little longer.
While I’m certainly no scientist, I’ve heard that these types of rings displace a bit more water than a smooth-bodied worm. This may be the reason so many anglers are having success with the quiver in dirty water as well. The bass may not be able to see it very well, but apparently they can feel it.