Thumb, finger, top, and side weights are static measurements of the amount of imbalance in your ball due to the weight block and its position relative to your grip. These imbalances have minimal impact on modern balls due to the high density, center heavy cores. However there are still legal maximums for these imbalances. If you have more than 1 oz of finger weight after drilling the ball is not in conformity. As stated in the last post this can generally be fixed by drilling deeper finger holes.