self promoting my youtube channel

What do you guys think about self promotion in the comments section. Is a little bit ok. How about promotion on a channel that makes similar content as you. Does it help grow a channel or hurt a channel more.

So recently I noticed a kid with a new vlogging channel that has been self-promoting in a lot of the top travel vlogging channels. He makes a comment thanking the YouTuber for the inspiration to start his own channel, and then he logs onto the same three accounts every day and gives his own...