The light spectrum of a resource satellite is inherently limited. It can only distinguish ten or so different categories of objects from the surface. Yet there are countless objects, and if two things react similarly to the same wavelength of light, the satellite may just lead to confusion.
資源衛星本身所有的光譜波段有限，只能把地面物體大概分成十幾類，但是地表物體千千萬萬，如果兩個物體對光的波長反應相近，衛星就可能「張冠李戴」，發生誤判。