You pose an interesting question Guenter. I doubt there is only one answer, but here's my take:

1) Some people make a real effort to participate in the forum by posting and commenting on other people's songs. In the spirit of payback, people are more inclined to listen and reply to songs posted by people who have interacted with them in the past. So, interest in other peoples' songs can lead to more interest in yours

2) By experience, you eventually decide for yourself which contributors tend to create songs you like. (and which ones don't) Once that decision is made, you'll be more likely to give songs from your favorites a listen.

3) When I see a song with a lot of listens, it often indicates that the song is worth listening to, so I listen too

4) the same is sometimes true when a song has lots of comments (favorable)... but lots of comments may also mean that the song has led people to suggest improvements

5) there is a tendency not to comment when a song doesn't bring anything "new" to the table. It doesn't mean the song is bad by any means if people don't comment (in fact if its bad, you're likely to get comments on how to improve the song). A song that is created by adding chords and generating the song with no tweaks is something that anybody with BIAB can do. Technique that goes beyond the basics almost always gets people asking how the composer did it. And that's when this forum really gets interesting.

6) People who experiment by combining various styles you wouldn't expect to sound good together also tend to generate a lot of discussion and comments

7) People who post a lot of details about how or why they made various creative decisions also tend to get additional comments, if not on the song itself, then the comments may get directed toward the additional information

8) some people only comment on certain genres, some tend to comment on clever lyrics, some comment on emotional impact, some of quality of mixing, how well the vocals sit in the mix etc etc

I'm sure there are a hundred other reasons I haven't addressed, but these few thoughts may partially address your original query

https://www.dropbox.com/sh/ey71h8ep047758h/AAC12jNM0Hz9Q8zsh5iDeqNHa?dl=0