Recently in the main site, I visited the users tab, and there I searched for "Subhadeep Dey", and it showed two results, this one and my own profile, and in both the cases, the username is totally same.
Though the other user has not participated in the site (just made an edit in Stack Overflow), and as an user, he is older than me; but in future, suppose he becomes a noteworthy member, then if other users ping "@SubhadeepDey", who will be informed as the "response"?
From the Meta Stack Exchange How do comment @replies work? thread:
Matching is performed in reverse chronological order, so if five people named John are participating, @john will match the most recent John.
Note that only users that have somehow participated in a post receive notifications of @replies. From the same answer, the complete list of the types of users who receive these notifications is:
The author of the post. [The author is always notified when comments are added by others to their posts.]
Any user who has a visible (non-deleted) comment on the post.
Any user who has edited the post (does not include pending or rejected edit suggestions).
For questions: The moderator or gold badge holder who closed or reopened the question. Users who have closed or reopened a question without a binding close vote (i.e. without a gold tag badge or a moderator vote) cannot be notified.
For questions: any user who set a bounty on the question (current or expired)
