Comparison of CatWISE2020 magnitudes fitted with (without) accounting for proper motion, w?mpro_pm (w?mpro), based on the sample of T and Y dwarfs shown in Figure 2. As the total proper motion (horizontal axis value) gets larger, a greater fraction of flux is “missed” by w?mpro, resulting in w?mpro magnitudes that are systematically too faint. We therefore caution that it is important to use w1mpro_pm and w2mpro_pm rather than w1mpro and w2mpro for objects with total motions ≳1″ yr⁻¹, even though w1mpro_pm and w2mpro_pm are not the default CatWISE2020 fluxes provided via IRSA.