Why youtube change my custom thumbnail?

Why youtube change my custom thumbnail after I upload the video? There is a bug or something else?
There isn't a problem for 10-20 minutes... and after that the thumbnail changes to a random image from the video...
The niche is hot chicks, but there isn't any nudity in video or in my custom thumbnail...
Maybe there is an ai which thinks that there is too much nudity on my thumbnail or this is bs?
I reuploaded several time and there is the same problem every time...

Upload a thumbnail without any people in it. Just the title or whatever else and see if it's still getting changed.

Yes maybe I need to test more... It's very weird...
Only happens for me...?
With my previous video it was the same problem...(same type of thumbnail) but after 1 reupload my custom thumbnail didn't changed automatically...

Now I reuploaded my new video 4 times and the same problem every time...

I dunno if we have the same problem but I have issues with the thumbnail too.
Basically when I search my video on YouTube the auto-generated thumbnail is the one used and not my custom thumbnail.
However if I go to my channel the thumbnail is correct, it's also correct for when I share the video on other sites.

Again, the issue just happens when searching my video on YouTube.
Some keywords search results uses the auto-generated thumbnail, and some keywords it uses my custom thumbnail.
It's just pretty annoying especially if you've put thought on the thumbnail.

This might give light though as to why: (Find in the page, "Why are my custom thumbnails disabled?")
https://support.google.com/youtube/answer/72431?hl=en

Then I've read YouTube does some A-B testing too regarding how custom thumbnails impact a video.

lmarton said:

The niche is hot chicks

Click to expand...

I have dome that niche myself and this happens quite often. Before yhey didnt remove the thumbnail but nowdays it sucks.
Ho are you planning to monetize this kind of content?

lmarton said:

Why youtube change my custom thumbnail after I upload the video? There is a bug or something else?
There isn't a problem for 10-20 minutes... and after that the thumbnail changes to a random image from the video...
The niche is hot chicks, but there isn't any nudity in video or in my custom thumbnail...
Maybe there is an ai which thinks that there is too much nudity on my thumbnail or this is bs?
I reuploaded several time and there is the same problem every time...

Click to expand...

It is not a bug its your niche it used to happen with me too in hot chicks niche

I have the same problem , any solution or trick ?

I heard that YT has AI in place so they can detect the source of the elements in the thumbnails. That's all I know. Maybe ur thumbnail contains some pics downloaded from a "Sketchy" site.