They Wasted a Perfectly Good Line Art

Some artists are great at drawing but not so expert at colouring; in Japan, this is largely due to manga being mostly in black and white. The most extreme cases make you facepalm and think "This gorgeous lineart deserves sooo much better!". This isn't a trope about bad artists -it's about the ones who can draw but can't colour properly, or at least whose linearts are much better than their colouring. Alternatively, the coloring work can be done by a separate person, who is either totally incompetent or has different ideas to the line artist. This often gives an "off balance" impression.

Please keep your Complaining About X and justifying edits out of this trope. Part of this trope is subjective and some examples are bound to be controversial. If you think an example really doesn't belong here, please bring it to the discussion page. Also keep in mind that you can genuinely appreciate and respect an author and still think their colouring isn't as good as their drawing style.

Of course, the trope title is an allusion to They Wasted a Perfectly Good Plot.

Comic Books

 * The classic Batman story The Killing Joke has garishly bright coloration upon its original release. The 20th-anniversary edition was recolored by original line artist Brian Bolland in an attempt to fix this. The recolored version gives some disturbing new details, like how when the Joker emerges from the chemical vat, his eyes were supposed to be bleeding. The original version colored the blood white, making the reader think it was just chemicals flowing down from the Joker's face.
 * Not tears? (From a hysterical breakdown and chemical irritation)
 * V for Vendetta was originally released in black and white, and then recolored by a different person. With watercolors. In quasi-impressionistic colors. Without paying attention to the lines.
 * John Ridgway's black and white art in the Transformers Marvel UK comic is very detailed and realistic. About half the pages had colour added in the original release, and they were all completely recoloured for the American re-release; in both cases, the colour took out a lot of what made it impressive.
 * And on the Marvel US side, the colorist for the entire run, Nel Yomtov, is often given flak from Transformers fans who feel he degraded everyone's art, for reasons ranging from frequent and large-scale use of monochrome block coloring to numerous outright errors.
 * While Frank Miller's art for The Dark Knight Strikes Again wasn't exactly gorgeous, the colors were often garish, which is a stark contrast to the muted coloring of the original (which was done by the same colorist).
 * This trope applies to much of the art from Neil Gaiman's The Sandman, but most especially the amazing artwork from "The Season of Mists"; Ty Bender's non-fiction "Sandman Companion" featured excepts of the same artwork without the hideous colouring, and the difference is astonishing.
 * Leah Moore's The Trial of Sherlock Holmes has horrendously garish colours over line artwork that is clearly noirish and evocative. The result is a resounding mess.
 * Elf Quest -- twice. The colourised Marvel Comics reprints were patchy at best, and the new computer-coloured versions are incredibly garish and obscure a lot of the original black and white linework.
 * Edwin Biukovic is known for having great detail and just all in all being very good at rendering faces and crowds. But compare this page from the comics version of The Last Command to this page from The Phantom Affair. The latter's not terrible, but it's more heavyhanded, and faces are often weirdly dark.
 * Quite a bit of Dark Empire is drawn in a rather unusual, stylized way. However, the colorist made some very odd choices, most notably deciding to tint nearly every page in some specific color and being overwhelmingly dark. Sure, a comic where Luke goes to the Dark Side might be expected to have dark colors, but there should be enough light to make things stand out.
 * The vast majority of the Disney Mouse and Duck Comics, at least in the United States. Characters will change the color of their shirts between panels, entire characters will be rendered in one color, gradients are used like they're going out of style, and very little background art is colored with detail. This is especially prevalent in Don Rosa comics, where the intricately detailed artwork is half the appeal.
 * The US Marvel Transformers run is infamous for this. While some of the artists were not very good in the first place, Nel Ymotov's lazy colors only served to worsen them. And there were some great artists on the book- William Johnson, Don Perlin, Herb Trimpe, Geoff Senior and Andrew Wildman, and their lineart deserved better.
 * More up to date (The IDW Transformers Run), in Escalation and part of Devastation EJ Su's lineart is colored by a fairly unimpressive colorist. Later, a much better colorist takes over and the difference is like night and day.
 * Archie Comics Sonic the Hedgehog contains a variety of examples, the comic not being exactly known for tight quality control, but a few do stand out. Any issue where Frank Gagliardo(sp?) colored Steven Butler's art brings this to the front - especially at the start of the Chaos Knuckles saga, around issue 90. Between just plain not knowing what color the characters were (the infamous green-clad red Gala-Na, giving Amy purple eyes instead of a shade of green, etc.) and painting the whole landscape of the echidna city of Albion in a dull gray, it just didn't do justice to Butler's tight, flowing art style. A more recent, though *slightly* less jarring example would be the whole "Enerjak Reborn" arc - while Jason Jensen is not usually a bad colorist by any means, the bright, vibrant, nigh shadow-less style he was using at the time felt a tad inappropriate for the darker turns of the story, making them feel overly light and cheerful.

Manga

 * Katsu Aki (Psychic Academy, the Vision of Escaflowne manga, Futari Ecchi, etc). His drawings are made of awesome, but his colour covers tend to look like he just used the very basic functions of Paint Shop Pro and never finished. He got better in recent years, but the contrast used to be very striking. Examples from Psychic Academy.
 * Some works by (ack!) Osamu Tezuka, such as Swallowing the Earth.
 * Koji Inada's artworks for Dragon Quest: Dai no Daibouken. The colouring isn't bad, but it isn't as good as the drawings.
 * A similar point could be made about Mohiro Kitoh (Naru Taru, Bokurano) and Lynn Okamoto (Elfen Lied).
 * Ryu Fujisaki from the Shiki manga.
 * These days, looking at Monkey Punch's (creator of Lupin III) experiments with Photoshop made his usually excellent lineart look soft and dated.

Video Games

 * A similar point might be made about the doujin game Hana Ki Sou.
 * The unlockable sketches of assorted Mooks and townspeople in Sonic Unleashed look a lot more impressive in sketch form.