If you have a Park or Unior truing stand, they can go out of dish alignment pretty easily. Not ideal, but this Unior Centering Gauge tool helps you quickly and efficiently pre set the dish on your truing stand. Just loosen the set screws on your stand that control dish, stick this thing in the axle slots of the stand, and tighten until there is just a tiny bit of play, like ¼ of a mm. Then using the truing calipers as a guide, use this tool to reset the dish. It’s like a perfectly dished wheel, but made out of a huge chunk of aluminum, so it’s really accurate.
Redishing takes about 30 seconds. I do it before each wheel build, and check it again toward the end of the build, and of course use a Dish Gauge to really make sure nothing fishy is happening.