It's all a matter of the quantity outweighing the quality here at writing.com.
Now don't get me wrong, I have nothing against the genre. Indeed, I have originated and contributed to many of the ones that are out there, and there are some very fine pieces for those that take the time to look. (This would be a place where I would plug some of those that I think are worth a look, but I have a feeling that this is neither the time nor the place.)
But why should those interested have to take time to look? To wade through pages and pages of contentless typo-scrawl that is of no worth to anyone? Because people keep on creating more.
Clearly, the answer is to put a stop to the deluge of new items that just take up space without providing anything worthwhile for a reader. So one has to look at what sort of thoughts might motivate a person to perform such an act.
Well, the first reason is pretty obvious; an interest in that little thing called macrophilia. No prizes for that one. These people, interested for one reason or another in the concept of very big or very small people, come to writing.com looking for something to titilate and entertain them. They find the static items greatly outnumbered by the interactives to which a community can contribute as a whole, and they think that they may like it here.
What happens next - the second reason - is where it all goes wrong. Having seen the long and successful interactives, they get it into their heads to start one of their own, which will bring other authors flooding to them to add here and there, and provide another exciting story for them to read.
That is the problem, the difference that sets these people apart from true authors. They just want to read something, without contributing themselves. Now, there's nothing wrong with that; browsers of writing.com are more than welcome as far as I'm concerned. But for such a person to start an interactive with no intent of adding to it themselves, merely expecting others to do it for them so that they can enjoy the results, is just wrong.
That's why these interactives have so few chapters. The creator has to throw out a few to get the ball rolling, and then sit back and wait for others to turn up and add. In the hopes of snaring as many people as possible - and also because a tightly-focused narrative isn't high on his/her agenda - these interactives will also quite often feature the first few chapters dominated by inane choices, deciding characters involved (although I use the term 'character' loosely in this sense), location and so on. Hopefully most of you will know the sort of story I'm talking about now, and I won't have to elaborate further.
These stories, the ones created by those who want stories written to order rather than to write them themselves, are squeezing out the genuine innovations, the ones with sharp new ideas for plot and character, and are driving away the authors who may be interested in creating the same. If only I could dare to hope that this decline may one day cease.