New users often don't understand that tagging system so I usually leave a comment. Some also misuse it to try to get "seen". We're just trying to keep the tags "on topic" so it makes it easier to find content users are interested in. You can edit/change any tag but the first one after you post.

It is encouraged to only make one #introduceyourself post but sometimes users like yourself will make two when they have been around a while and want to tell the community about themselves.