Update README.md

README.md

@@ -28,7 +28,7 @@ Palettes can be sorted by hue, luminance and chroma, using the HCL colorspace an
 
 * Can generate palettes of N colors relatively quickly.
 * The palette is generated by first grouping colors into N intensity levels and then use the median color of each group.
-* The generated palette is not 100% optimal, but it's usable.
+* The generated palette is not 100% optimal (based on how the human eye is more sensitive for green etc), but it's usable.
 * Can export any given `color.Palette` to a GIMP `.gpl` palette file.
 * Can export any given `color.Palette` to a Photoshop `.act` palette file.
 * Can convert True Color `image.Image` images to indexed `image.Paletted` images.