- OP asks a question.
- Some other user leaves a comment.
- I leave a comment asking a follow-up question.
- The OP leaves another comment answering my follow-up question, but doesn't @reply to me.
In this scenario, I don't get notified of the new comment.
Of course, when someone @replies to anything, the user in that @reply gets a notification. But when a follow-up comment doesn't contain an @reply, the previous commenters have no idea that there's new information. Sure, the OP should @reply, but when they don't, it could leave them hanging without further help. Is this just the way things are meant to be, and it's "tough luck" for the OP if they don't @reply?