Nope, I had worked on other personal comics and commissioned comics before that. Nothing for a company though. I started when I was 13 and I am definitely no longer 13 now haha.
2) What was your episode schedule while it was on Canvas? Roughly how many panels and how frequently did you post?
I've done once a week before and I've also done once every 2 weeks before. Both have worked for me in terms of gaining readership and Webtoon's attention. Consistency is a factor, as everyone has said. And since I worked on my comic while I was a full time student or when I was full time working, I did my comic on a rolling basis the week before it was due up, meaning, sometimes chapters were shorter cause I just didn't have the time that week. The never ever dipped below 27 panels though and I aim for about early to mid 40's.
However, I also think the pacing of a chapter is important, so if I have a chapter where lots of things happen, then I'm going to need to extend that chapter so it ends at the right time. Sometimes that meant a chapter went upwards of 70 panels. But that was rare.
3) Why do you think your webtoon got chosen to be featured? Do you know how that was decided? In my mind it's just a webtoon editor browsing through canvas, finds one, asks his higher-up if it's okay, then emails the creator...
I'll be honest, I believe my situation is a bit different from others, it took a long time for me to move to Originals. Take Lost in Translation for example, they are were in a similar situation to me in the sense that they had a huge following and had been posting for years before they went to Originals. Having a comic move from Canvas to Originals after more than 1 year is rare. Nevermind 2 years or more.
Most comics are going to be found by editors just reading through canvas. I don't think that was how mine was found... exactly. They didn't actually tell me the specifics, they just said an editor suggested my comic. But I also know my comic had been suggested before and not been taken on, because I've worked with Webtoons before and drawn panels as "one of the editors is a really big fan", and they said they'd bring up my comic to the others. I didn't get a contract that time.
Ultimately, the person who contacted me to offer a pitching opportunity was the Head of Content at webtoons.... which I don't think is usually his job (but don't quote me cause I haven't asked my friends who contacted them to be featured before, who knows, maybe he contacts all the new comic artists).
I can't reveal anymore without it being obvious which comic I might be, but there were other really weird factors too, and in conclusion, my comic's relationship with webtoons is a bit of a mixed bag and I have no idea what made them decide to eventually offer me a contract. XD
4) Why do you think some series get original offers really quickly and others take years?
I agree with all the points @ninjashira has made, and I've added some points below that generally just compliment what they've said since all of these things kind of feed into the points they made.
Uniqueness, Marketability, how confident the art style is, how clear the story progression is, popularity, how consistent they are. I think those are the major player in my eyes and I ranked them from most important to least important.
Uniqueness: if you have a comic idea that could be replaced by 10 other comics, they won't care to sign your contract. Especially if it's similar to a comic they already have. Webtoons does care a lot about story, good story writing and variety, it's not all about romance, and that's what makes them stand out from places like Lezhin and other similar sites, in my opinion. so you want something that's fresh and a unique spin on topics.
That's not to say you can't do a romance or a fantasy. But think about it this way, it just means more competition. If you put your comic into the horror pool, you're gonna have a much smaller pool of competent and marketable comics to compete with than if you had a romance comic. That might make or break your comics opportunities. But also, don't let that be the sole reason you decide on a genre, you definitely want to pick a genre you enjoy, but just be realistic about it.
Marketability:
If you comic is unmarketable, they won't take it because it won't make money and that's just hard facts. Or they'll ask you to change it to be more marketable. 18+ things are really not preferred and ads don't like that kind of stuff as well. Again, there are exceptions and there are loop holes, but if you're really looking to get signed, and this is the cast for many companies, they don't want to have to deal with the work of having to bring your comic up to mainstream acceptability.
Confident art style:
Webtoons want's established artists, not in the sense of popularity, but in themselves as an artist. and that is important. You need to know what your drawing, how you draw and what exactly it is that you as an artist brings to the table. They'll help you and give you suggestions, but fundamentally, you need to have stability as an artist. In both anatomy and in style. Because it's a lot of work to take on an artist that doesn't have their fundamentals down and that could mean a delay in getting a comic launched so overall, they won't bother with an artist like that.
Story:
Again same as confident style, they want to know they can trust you to have a story read and to finish a story. You don't need to have the entire story in your comic, but they need to be able to see that things are being planned.
Popularity:
This does matter only in the sense that popularity helps but not being popular doesn't hurt... if that makes sense. Because being popular means you're probably pretty marketable and you'll bring in people.
consistency:
I put consistency below popularity because I've seen friends get picked up after having the worst upload schedules or after only a few episodes cause they went big FAST, so really how can you even tell if they are consistent or not. however, for comics that don't get picked up 3 days in (haha ) consistency is again showing them they you know what you're doing, you are reliable, you are stable and you don't need them to prop you up in order to be a comic artist.
I think I digressed a bit... sorry, but essentially, those are some of the factors that go into how a comic is picked up, in my opinion.
Good luck!