When using the Spot & Patch, Crop, or Redeye adjustments, you may notice that the target and selection overlays do not always appear. That's because selecting a palette in the Adjustments Inspector does not automatically force the selection of the corresponding tool. To see the overlays, simply select the corresponding tool in the toolbar.
This arrangement allows you to tweak your last modified selection further without giving up your current tool. When you want to further adjust an earlier selection, just click it with the proper tool to reselect it.