To throw another loop, there are also nuts that have screw holes drilled and threaded in them. A washer goes on the outside of the nut, keyed to the spindle, with holes drilled in it. Line up a set of holes, put two screws in 180* apart. My personal favorite, my nissan has this. It gives more options. sometimes with a castellated nut, one seems loose, and the next feels too tight. I always err on the tight setting, bearings will only loosen up.
I don't think it matters much how it's done, really.