There are a lot of people who post videos on Youtube. Some just post videos for themselves and don’t expect anyone else to see them outside of a few people that they know. Others upload videos for everyone to see with the hopes that as many people as possible will see the videos and share them with their friends. They also hope that people who see these videos will subscribe to their channel. Sometimes simply uploading videos isn’t enough to get subcribers, and you have to buy youtube subscribers.
I have my own channel where I upload videos of different animations that I make. When I created the channel, I did it so that I could make some money from ads on each video. I wasn’t getting that many viewers on my videos. At best, each video would only get a few hundred views, which only amounted to a small amount of money for me. I decided that I had to spend some money if I wanted to make more money from Youtube.