I haven't really come for enough in the story I published for people to be interested in adding to it. And I'm pretty new here too. But I have added to other stories so perhaps that will be useful information. The stories I tend to like to add too already have a lot of chapters. The first time I contributed to a story it hadn't really had an update in a couple of year but I liked the setting and it was detailed enough to make me feel able to add to it while providing enough freedom to develop a plot or add new elements. It felt like I contribute to something bigger than what I could create on my own over a limited amount of time so that's what I liked about it. It also already had a following of readers so it brought in more views and likes than what I'd get on an independently published story which is rewarding. After writing and establishing a presence on certain branches. IT brought back old readers and newer ones too which was a nice development to see and there were two authors who added to the chapters, one of them were interested by an element which they took advantage of an element I'd introduced to pursue their own fetish, and the other one liked a character I'd introduced and wrote a branch with that character. Verry fun experiences. I've added to a few other story with anecdotal chapters but they've all been deep enough for me to gain a feel for the story world and the charchters. If your story has particular characters It'll probably need a bit more for readers to feel like they've become acquainted with them and developed enough of an emotional connection to care where the story might go next. I think a few stories have their own discord which encourages readers to interact with eachoterh and I guess stimulate author's to add to it. But I've never joined or been part of this so my understanding of it is not so clear. My experience is limited, but hopefully this was helpful.
