This has been going on in comics almost since the comic book miniseries took off. Camelot 3000, a series intended to be 12 monthly issues, started in December 1982 and ended in April 1985, with nine months between the last two issues.
And then there was invented "Buy the Deluxe hard-cover and Archive Binge the whole thing in one night", and there was much rejoicing.
Kevin Smith might as well be the trope namer. Various comics series of his have been met with ridiculous delays, with Spider-Man/Black Cat taking three years to finish and Daredevil/Bullseye, having been started in 2002, remaining unfinished to this day (Ten Years!). In addition the second part of the Widening Gyre has yet to come out.
All-Star Batman & Robin The Boy Wonder started in 2005 and took until 2008 to reach issue ten. A new six-issue mini-series would be done by the team to wrap it up, but even that is running late.
Jim Lee once stated at a comic con that all the pages were complete, DC were just holding back the series in the face of the New 52 and Lee's prominent position in that reboot. Batman: Europa, which was also intended to feature art by Lee, was also held back.
Most annoying, Batman: Europa actually got solicited, DC put ads for it in all their comics and it seemed to be on track just a month before the scheduled release... and then it vanished.
To celebrate their 10th anniversary, Image created Image United, intended to be illustrated by all of Image's founders and written by Robert Kirkman. As of 2012, close to two years later, they're at issue 3, with the next two issues being about 60% complete. There were many, many jokes about this being very appropriate for the company's anniversary.
Circles originally began four issues per year. Now the rate of issue appearance is akin to Berserk's.
Happened to Ambush Bug: Year None, with a several month long gap between issue five and the finale. AB being the Meta Guy he is, this was thoroughly lampshaded in the issue itself, which was actually called issue 7 (with six being nonexistent) to further make fun of its lateness.
The print comic Battle Chasers was intended to be Joe Madureira's big break, and fans were extremely eager for it. Unfortunately, Joe also bragged in a magazine article about all the fun stuff he and his staff could do in their offices that were not in the slightest bit connected to getting a comic on shelves; the series was eventually abandoned altogether, along with the majority of Madureira's career. Battle Chasers has practically become a phrase meaning "comic that cannot meet its schedule" in the comics industry.
Due to scheduling conflicts, Dave Gibbons' reboot of Rogue Trooper ended up being told in groups of 3-4 six-page installments over 37 weeks.
Comics written by Allan Heinberg tended to be horribly delayed.
This seemed to be a recurring thing with Grant Morrison. Both Batman & Robin and Return of Bruce Wayne faced numerous delays from the summer of 2010. It got to the point where neither series had an issue released in August. This had also led to comics taking place after Bruce's return (The Road Home one-shots) being released before the Return was complete.
Planetary by Warren Ellis and John Cassady released 27 issues in TEN YEARS. The script of the final issue was apparently written over two years before it was published. This was in large part due to both creators working on other titles for other companies at the same time; Ellis was by far the worst offender, as during Planetary's run, he worked on at least twenty other books.
It wasn't just work: at one point, a delay began because Ellis was ill. Cassaday, not unreasonably, took on another job to keep earning a crust. By the time Ellis was well, Cassaday was ill. By the time Cassaday was well again, Ellis was too busy with the other work he'd taken on to keep earning. Rinse and repeat.
Platinum Grit is a bimonthly comic, the first issue released in 1994. They gave up on bimonthly a while ago - issue twenty came out in 2009. Or you can just say it's twelve years behind schedule.
Fans of Sasmira have been waiting for the release of the second episode since 1997. And by the look of it they aren't done waiting yet.
In the now-canceled Star Wars Rebellion comic series, the very first arc was plagued by a number of schedule slips. Issue four was released in late July, ending on a cliffhanger going into the final issue of the story arc. The conclusion to the arc was released in December of that year.
Ultimate Wolverine Vs Hulk #3. Scheduled for April 2006. Published in March 2009.
The Ultimates. The first 13 issue volume took 26 months from start to finish, the second equally long volume (for which Marvel promised that they had learned their lesson about keeping it on schedule) took 25 months.
Heck. It's a foregone conclusion that anything Bryan Hitch is involved in art wise will be subject to this trope due to Hitch being (in)famous for taking his sweet sweet sweet time drawing! The end result is beyond amazing, but still.
The Astonishing X-Men ongoing series took full four years to complete a 25-issue storyline. As the result, Shadowcat being Put on a Bus was spoiled by Messiah Complex: since its events couldn't take place before it, Kitty was nowhere in sight. The series was written by Joss Whedon and then Warren Ellis continued the trend. The reason is the same.
Occurred for nearly a decade with writer Kurt Busiek due to mercury poisoning; this mainly affected his work on Astro City, and eventually caused the title to go from a regular monthly schedule to periodic limited series.
''In summary, our tale makes clear That Patience is a virtue dear. So, gentle reader, know your place, And don't get on our ***ing case."
19 issues of The Red Star comic have been published since 2000, and the storyline is not finished by a long shot as of this writing. The latest three issues came out in roughly one-year intervals in 2006-2008, and who knows when the next one arrives.
Every single issue of CLiNT has been delayed due to the artistic team on Kick-Ass 2 having to prioritise The Avengers. It got so bad that in issue 10, it was announced the comic would be shifting from a monthly to six-weekly schedule.
Civil War. Issue #4 was pushed back a month and #5 wasn't released until two months after that. Apparently this was to give Steve McNiven more time to finish the artwork. That doesn't seem so bad, but remember, this was a Crisis Crossover. A number of tie-in issues (either other minis or regular titles) that were completed on-time were held back so as not to spoil developments in the main mini-series.
In fact, during the period when Marvel had Spider-Man temporarily revert wearing the black costume to promote the third movie, he actually went through this in the companion books first, while the main storyline in Amazing that had him adopt the new look had yet to be even released since it was still wrapping up the Civil War tie-in that led to said story.
David Lapham managed to produce only 40 issues of Stray Bullets over the course of ten years. Towards the latter part of that time the slip had gotten so bad that the comic was coming out roughly annually or biannually. It has since been declared an Orphaned Series despite Lapham's insistence on eventually returning to finish it.
Geoff Johns, Richard Donner, and Adam Kubert's "Last Son" storyline in Action Comics. It was five parts and took nineteen months to finish. Part of the reason was Kubert needing to take some time off because of health issues. Because of the delays, by the time it was finished not only had Johns and Donner finished their second arc before their first but Johns had already switched to collaborating with artist Gary Frank. In fact, DC had a huge problem regarding this around 2007, especially in all of their Superman books. The promised conclusions to several storylines wound up being delayed for either a future issue or a giant-sized annual, causing stories to get wrapped up months later than intended.
Jay Faerber's Gemini is a five-issue miniseries that started in 2008 and followed a "whenever we feel like it" schedule, with its fourth issue published in November 2009. The fifth? Well, Faerber claims the fifth and final issue has been written for some time, and that it's still "in the works, theoretically."
Danger Girl became somewhat infamous for this near the end of the original series, with several months passing between issues. Artist J. Scott Campbell would later take it a step further, seemingly abandoning Wildsiderz, and really sequential art in general, after the second issue.
The third installment of Phonogram, "The Immaterial Girl", was pushed back to sometime in 2013 or 2014 after its initial announcement due to Kieron Gillen and Jamie McKelvie's growing workload with Marvel. They have stated that it will be released once their workloads ease up.
Not to extreme extents, but each issue of the first Story Arc of My Little Pony: Friendship Is Magic (IDW) have had to be delayed from their original scheduled release date. The first issue due to demand for the comics far exceeding expectations, the second (with a bunch of other IDW comics) due to a union strike, and the last two due to customs inspections.note IDW comics are printed overseas.
Runaways suffered from several schedule slips during Joss Whedon's run on the series. This proved to be especially disastrous after Marvel decided to reboot the series with a new creative team who began working before Whedon had finished, and thus were unaware of some of the changes that Whedon made (like Xavin becoming female.) The resulting continuity issues in the new series may have been a factor in the its cancellation.