I added one to my ball. My Father-In-Law came to visit us from Honolulu and we went to Pro-Shop looking for a used ball. The shop owner has severe Rheumatoid Arthritis, even has a service dog, but still bowls. He had my FIL try his personal ball that featured a pinky hole and was 14 lbs, he was using my 15 lbs ball to let the Shop owner watch his swing. Anyhow, My FIL asked if he could buy the owners ball from him and he did sell it. Obviously I had to try the ball too after that and I then realized having a pinky hole felt more comfortable and natural to me too, so I added one to all my bowling balls after that.