Mentoring started on wikis we work with because some people added their names to the list of mentors when we publicized the deployment of the features. However, we can't be sure that this group of users will auto-renew. What we are sure of is that a few users already removed their names from the list, because they discover that they dont have time or patience for being mentors.
The software should invite experienced enough users to become mentors.
Being a mentor requires two skills:
* being able to have empathy towards newcomers
* have a good enough experience of the wikis to help newcomers (or find someone who could help).
The notification could be triggered when a user raches some conditions, such as:
* a certain number of edits in the mainspace (to characterize activity)
* a certain volume of edits in the mainspace (to characterize constructive edits and avoid people who think quantity is a better measure than quality)
* a certain number of edits in discussion and communities namespaces (to show interaction)
* a certain number of positive diffs (showing constructive edits)
* a clean block log
* ...?
These conditions should be defined with inputs from various community members, to find the average values.
Of course, this is not a replacement for local outreach performed by communities.