The content of a video determines how successful it would be on YouTube. Alot of factors determine how successful the video will be. Here are some:
The quality of your video is important, you do not want to give out poor quality videos, this will make viewers leave in the first few seconds of the video. What’s even worse is that they might give you a thumbs down, and too many of that will rid you of viewers and followers.
Your intro is also very important, the impression you make at first determine if your viewers stay or leave.
Keep it simple and straight to the point, do not beat around the bush, go straight to the point. Including background music also help to grab the attention of viewers and the video wouldn't be boring.