Time and again, we are seeing when a new short form video is shared on YouTube from a respective channel, one of the older videos from that channel that was trending on the YouTube Shorts Feed falls off or is replaced. If you are looking on your YouTube Studio app, it might look like this:

Notice how the video that received 22.5k views completely fell off when the 15.1k video started to take off. Is this a coincidence? We think not and here is why.
It would make sense that the YouTube Shorts Feed would only allow a certain “number” of videos to be trending based on the success of the YouTube Channel. PageRank matters a lot, in terms of SEO. Remember that Google owns YouTube and PageRank will always be the way in which Google ranks content.
If a YouTube Channel has a Pagerank of 5, it may be able to have five (5) trending videos. If the YouTube Channel has a PageRank of 3, it my only get one (1) trending video. Google and YouTube have been fighting spam since they were created. This would be an incredible way to quickly and effectively reduce spam.
Until your YouTube Channel is worthy of having multiple videos trending on the youTube Shorts Feed, you are limited. This will make creators continue to put forth effort and produce high quality content.
Unfortunately, there is no rubrik to explain how many videos your YouTube Channel can have trending on the YouTube Shorts Feed. In our testing, we have noticed that the more something is in the news media or getting searched, the higher the number of videos your channel can have trending in the YouTube Shorts Feed. If you are a F1 content creator, you could have 10 different videos trending on the YouTube Shorts Feed on the Sunday of race day. During the off season, it might be the case that only one (1) video trends on the YouTube Shorts Feed.