Colour vs. monochrome

I just noticed post #161604, with rather curious deletion reason. Artistic quality of that pic aside, I'd like to point out that having a coloured version is *NOT* a reason not to have the sketch / b&w version, and in particular, it's not a reason to delete anything.

Seems they deleted their own, but yeah, there's no reason to delete a sketch because there's also a colored version. Just parent or something.

Personally I like as much to have image in black and white that color.Would be damage to remove them because it already exists color.