i dont have plans to discontinue spire, but after 3-ish years there IS a sort of disconnect you start feeling from the story. its not necessarily a negative feeling? but it feels a lot less personal than it used to. my guess is that its from that?
Top reasons I encounter are:
Injury of hand/shoulder/arm due to repeated stress. Be sure to draw in a way your body can handle!
They're a pantster and they got to a point in the plot that they haven't figured out. The difficulty pushing through without retconning is overwhelming. Plan your story completely before you start.
They're not getting the recognition for their work that they want. So they drop it and try again. This isn't a bad idea, but be sure to take away some teachable moments from your experience so you don't wind up making the same mistakes the next time.
8 years is a long time and people can get bored with the world and characters they've created. And if they're not getting anything out it, they're just laboring over nothing basically.
You should ask them specifically why, or if they could go into more detail (find their contact info somehow)... Might be therapeutic and cathartic for them as well as you... I'm curious to know too.
Making comic is boring honestly, but i don't know what else i'll be doing besides that anyway
edit; just realized i've been doing this shit for 4 years now lmao, felt like wasting time after this long tbh
Honestly, I think it's burn-out.
From what I've experienced personally, it can stem from various things
- Not getting recognition: fans that leave comments besides hearts, single digit views and likes
- Obsessively thinking about it and working on it daily (I think this is number #1 problem)
And then it turns into a negative circle that you can't escape. You think about it every day, you work on it every day, you upload things on a weekly schedule or more frequently and get little to no return.
A good analogy is something I just told a friend of mine, it's like a restaurant. There's a long-time eatery closing in my home town and everyone's reacting with "aww that's so sad! I love that place!" and the owner literally is responding with "clearly you don't cause you don't come in and spend your money here". Be it comic or novel, or some other endeavour, if you constantly don't get any responses until you finally pull the plug - that's too late. Now, you can be a fan and go off and complain that your "favorite" thing ended, but if it's not supported, that's what happens.
iirc another example close to comic creator's home should be the mangaka for Yami no Matsuei, as the story goes so far as I've heard/recall: the mangaka suffered an injury of some sort, healed, came back to draw, and their drawing style went from a certain stylistic style many were familiar with (and could attribute to the late 90s and early 2000s, though I see it as gorgeous), and it transformed into something more realistic; THE FANS did not like this change, did not support this change, and stopped purchasing the new releases, so the manga was pulled and ended before the actual plot ending.
For my own personal experience, what makes me quit a novel (writing it) is that I'm just not creatively flowing with it any more. That's 1, or 2, I have ideas for other stories. And 3, I have multi-plot ideas that would segway the plot into different directions and I'm unsure which would be "best" to follow, and end up doing none, and just ending Cold. Turkey.
I have thought more than once to end Nearly There Nicely simply because of the lack of attention it seems to get from readers. Especially after my car accident in May 2017, I was deciding to adjust my mode into just editing what I already had and "just write to 90" so I could edit that, and end it at 90 cold turkey. It felt like no one was reading it, no one was enjoying it, no one was liking it, and no one was even seeing it: I was invisible. Now, don't get my negativity wrong, I still feel highly invisible on Tapas. The only change is a visual record of views and likes. I have at least two people hitting like on the updates. I do preach that "you should write for you" but if you (being me) aren't happy with what you have, either quit or do something to make it better. I happened to find Tapas around November or something last year, and thought "eh it'll probably be dead like everywhere else." My first month here hit 139 views, for just the first 10 chapters (and the 10 chapters I consider the weakest).
Writing, creating, comic drawing, drawing, cosplay sewing - anything like that - it's all a very isolating creation. If you live in an area like I do that's super rural and doesn't have much of anything going on, then you will be pressed finding ways to stay motivated. Every few days still I think about carting it all up and quitting. I can only explain that this urge comes from the daily illusion of "no one sees my stuff". I think about it daily, I work on it daily; How come daily it doesn't have a number of views that matches how many times I obsessively refresh the page? That obsession of focus, without taking any breaks from it, can lead to the depressive lows. That's why it's good to have focus, but just as important to allow your brain to focus on something else - some movie, tv shows, your pets, gardening, something that just isn't "omg my character is cooking so I need to cook what they're cooking omg I must make it perfect because they do!" and then you curl up on the floor of the kitchen because you burned your pan to a crisp. It'll be fine- just soak it and see if you can save it. There, there, hypothetical me, just don't leave the burners unattended.
I will say what kept me from quitting on my new comic was a change in my social environment. Both online and off. It wasn't just getting some encouragement, but getting specific support from sources that believed in what I was trying to do and could see the potential I didn't.
Real specific Hope just kinda outweighs all the things I've been struggling with.
Looking at the hobbyist vs. Professional aspect, I feel like rate of production probably plays a largish role as well (in regards to the concept of outgrowing a story over time).
With a serialized manga series you see the authors pumping out a chapter weekly in a lot of cases, or like monthly issues (which are roughly 1 chapter) of western comics. With this rapid rate of production it seems like there's a chance for the story and characters to grow more freely with the author over time. 2 years into a shonen manga's run you're several volumes in, a lot has happened to the characters, and they've grown as a result.
Compare this with the rate that most hobbyist comic artists can produce content: a lot of folks produce between 1-5 pages per week, max. 2 years in a couple of chapters may be finished and not a whole lot of story progression may have been made. The characters and story are largely the same as when you started, but now here's you: a few years older and wiser and wondering if it's still what you're interested in pursuing.
It's something I think about often in regards to my own work. I was literally the person that the article @punkarsenic linked describes up until about a year and a half ago lol. Since then I've started working on mostly one-shots that wouldn't take much longer than a year at most to finish, as well as writing/coming up with ideas for a longer series in the background. But I refuse to start the longer project until I've trained my speed to an acceptable level such that I might actually see it through in a reasonable time 
it'll already take a few years at best, but if it becomes one of those 8 year comics its probably not getting completed.
Dude, so that was! 
Jumps in time help with that: like start presenting the characters some months in the past, next issue in the present, next some months in the future...
I'm writting my novel that way but I still had not realized that fact. For me it's natural since I'm more intuitive than planner when creating, but I get it must be difficult for those who plan all the story at the start 
I mean, the characters don't stop being themselves, but that concept: they evolve with you, it's really important to keep in mind when doing long run projects.
My mind is blowed 
This pretty much one of my issues into making my comic. I try to consume my time with other things so that I dont obsess over my comic, but it always finds its way into the front of my thoughts.
I live in an very busy metropolitian area of a city and I still get like this at times.
I'm very scared of being "that author who goes on hiatus and never comes back".
The seasons why I would quit, are very simple:
-the story is a mess and I can't fix it: Basically if the whole thing turns out being incoherent garbage.
-It is making me sick or becoming unhealthy: This is supposed to be my happy place, not a project to get more depressed.
-Nobody cares anymore: In this case I can still make some art for myself and scenes I wanted to draw for so long, but I would quit the chapter by chapter comic format. What's the point of keeping a stressful schedule, work 16 hours per update if people are not into this anymore? I can totally start making random art that makes me happy without the burnout.
I don't want my comic to die without a conclusion 
Because I saw a mangaka schedule once and it looks like this.
Helps that they are guaranteed to be paid for the most part.
I think this is more about independent artists/comic creators.
They get paid yeah but it doesn't change the fact that their work hours is almost unethical. I'm just trying to show that comic artists/mangaka have it rough in many places.
Sometimes even us artists forget that comic making is a legitimate professional work and have high expectations for our projects. Some readers even demand us to have the quality of a studio product, when in reality we only make comics on the free time. It is hard to make comics, let alone doing them for free.
I would imagine depression and life problems play a major role here. It's hindered me many times.
But I'm currently homeless and I'm still working my arse off, sitting at my local bar with my laptop and writing and drawing like there's no tomorrow. For me, it's the only thing that keeps me going.
But for others... it's harder to keep up with when life problems pummel you, bills to pay, loved ones enduring strife, and personal depression, which is something common among most authors and/or artists. Creative folks often feel discouraged from trying, especially when they fail to garner their desired audience or when they see someone else gain a ridiculous amount of success.
Then, there are critics who don't try to be constructive. Criticism is very necessary, but some folks purposefully try to rip down your work and make you feel like a damn fool for even trying, and this is mental kryptonite for any creators who haven't yet developed the thick skin they need for the job.
Well first of all.. most webcomics are a labor of love. The creators aren't being paid to make them. I've had a webcomic that has been running for almost 8 years and due to the fact the writer and I both just had babies, yah, we are walking away from it for a while since there is just no time for a hobby right now. This doesn't mean that either of us can't survive in a freelance comic world. Freelance generally means you are a professional that gets paid to do gigs (but you aren't hired exclusively by one client). So, I know several artists that gave up their side webcomic in order to do paying work. The paying work pays the bills, the free webcomic does not. In fact, most successful freelancers probably don't even have time to do a free webcomic. Taking a hiatus is hardly an indicator if you can make it in the industry or not.
Though I am not a webcomic artist (Just now I feel like I have enough talent to do it, but I'm in my thirties and with a babe, two dogs, and my daytime career, I just don't have the time), there was one moment where I quit for...uhh...lemme check...
2008 to...2014. 6 years.
The reason I quite was because I had taken something someone really close to me said...very poorly. I am able to brush that off now, but man it was blow.
Sometimes life happen. It could be they are tired of their current work and want to try something else, or maybe they had a kid and just no longer have the time and need to adjust.
Pretty much this nowadays. I wanna keep going in on my story, especially since I just posted here, but now time and energy is at a premium.