TRENDING; A question

I don't get it. I barely care, but the metrics of this fascinate me, largely because I don't understand them
  1. When I go to li.st on a computer, I have a list under the Trending headline. Not high trending; 34 down.
  2. But on my phone it's not on the Trending list at all.
  3. Does anybody understand this?
  4. Has anyone else seen their list trend on a computer? Do you get a notification? I didn't.
  5. I had a list on the Trending list on my phone a day or two ago and didn't get a notification then, either. How about anyone else who's had a Trending list?
  6. I don't need the notification for gratification purposes, but I'm curious how this works and if I'm curious, I bet other people are, too.
  7. Ring in!!