What are the criteria to be considered a "first answer"?

Question

In the "first answers" tab of the review panel, I always assumed that it would only ever show the very first answer that a user posted to the site. Apparently this is not the case:

What are the actual criteria, out of curiosity? Does one of their posts need to get an upvote before it stops flagging them as "first answers"? Is there some sort of time period?

I'm also assuming this isn't a bug. It makes sense to me that a user can post multiple answers in a short amount of time at first, but it would also be good to know what satisfies the system.

Are the criteria the same for "first questions"?

Answer 1

If you look at the textbox on the right, it says:

These are the first answers of new users on Meta Stack Overflow.

Note that it says first answers and not first answer. So that means that all answers they ask while they're considered a "new user" is up for review. The question then is what counts as a new user?

From the /privileges page, new user restrictions are removed at 10 rep. So this means that a user with < 10 rep is considered a "new user" by the system even though they might have been around for a while.

I have taken this Source from: First question in Review isn't really a first question

And it will also answer your second question.

Answer 2

In addition to Somnath Muluk's answer, it should be noted that in the review queue:

A post is considered reviewed as soon as you and two other users have clicked the review button.

In addition to this reviews done by a moderator appear to be binding in the review queue.

So individual questions will disappear from the queue if two others have reviewed them first. This means that theoretically a users third question could be the first one that appears in your queue. However I believe that Somnath is correct that the requirement is 10 rep to stop the automatic adding of a user's questions to the queue.

I've also requested that users with 101 rep on a site (e.g. just the association bonus) are also submitted to peer review, however this isn't currently the case.