Michael Sherman was notoriously bad at coloring pictures, yet most of his art remains on e621 and it doesn't look like it's ever going away (several his images were deleted for quality reasons though).
Now, if somebody decides to recolor an image so that there're no longer gaps between lines and the fill, how can that not meet quality standards?
The post in question:
If you scale the image down to a resolution Mike usually used it's clearly higher quality than his colorings. The image obviously doesn't deserve its resolution, as there're no details, but I saw no point in downscaling if it's the resolution the coloring was done at and downscaling is performed by e621 anyway (to 600x600 I mean). Well, the image can be optimized, as indexed color would probably be enough, so file size shouldn't be an issue either (I doubt anybody cares about it though).
You can find the source on InkBunny: Nala with ringtailed raccoons by Mike Sherman (page 3).
Note that the image has been updated since it was reposted on e621. Now the lines are cleaner and there's a background (see Nala with ringtailed raccoons by Mike Sherman (page 1) ), so the there's no point in having the original recolor with noisy lines here, but I'm still interested how the quality is measured, as any of the 3 recolors are clearly an improvement over original Mike's colorings.
Compare to something like this:
Updated by Genjar