Articles for topics that don't have wide interest are difficult to maintain. If there isn't substantial independent coverage of a webcomic, it's hard to verify what's said about it is true, and much of what is written about it is unencyclopedic original research. What you end up with are articles written solely by authors or dedicated fans, who have a difficult time maintaining the neutral point of view. If a comic disappears and its fans lose interest (it happens a lot) we are left with an article we can't do anything with. To keep that from happening, we nominate articles for deletion and developed the WP:WEB guidelines.
Wikipedia is not where to go if you want to become well-known. Rather, it's a repository of what already is. Many assume Wikipedia is like a top 100 list, a good way to generate traffic for their favorite comics, but that just isn't true. We have over a million articles here, and unless a topic is already notable, it will just be lost in the shuffle. Ironically, about the only time a Wikipedia article generates traffic for its webcomic is when it's nominated for deletion.
An important point that should concern authors especially is anyone can say anything about your comic here. If it's known, there's a very good chance someone will quickly remove the defacement, but if it's not, vandalism can stick around for months. That's long enough to propagate to the many Wikipedia mirrors, some of which are never updated. If you do a Google search on our lesser known webcomics, you'll find many of the top results are from Wikipedia or our mirrors. How would you feel if they contained false information? I recall one webcomic article we've since deleted existed for several months as a personal attack on its author. If you googled the comic's name, most of the results returned consisted nothing more than that same attack.