'Revised Zone Rating (RZR) measures, “the proportion of balls hit into a fielder’s zone that he successfully converted into an out. RZR measures a player’s range, taking three things into account: the amount of Balls In Zone (BIZ) a player receives, a player’s total Plays Made, and a player’s total amount of Out Of Zone Plays Made (OOZ). It is, essentially, a simplified version of UZR. So it measures the range as opposed to the stat that is called range factor. Range factor is calculated by dividing putouts and assists by the number of innings or games played at a given defense position. For me, it seems there's a difference between speed and quickness.