For any scroll type chuck, as you go around the circle of the chuck, starting at the lead in of the scroll form, the distance from center increases. In order for the jaws to be centered on the chuck, the slides need to be ordered 1-2-3-4. The matching partial scroll form on each slide is machined with on offset (or not, mfr depending) to create a perfect circle of the bolt holes , and then jaw1 can be put anywhere, and the others mounted in order due to the previously described mfg process.
Some mfrs may not offset the slides or holes but machine the jaws for specific location, and these need to be matched slide to jaw. There a a few other ways this can be done, but it all about the scroll form radius constantly changing, and then how a particular mfr chooses to correct for it so the the jaws are perfectly centered on the chuck.