Can someone explain to me why and how bots are uploading chapters? I'm ignorant about this...

I also would like to know how this happens

I have no prove whatsoever, But basically according to all the notes I read from uploaders.
The bots automatically take from other illegal websites and post them here.
While uploaders usually wait 3 days if there’s an official release so the the artist can get some money then they post here.
Well that’s what I know and it might not be correct ╥﹏╥