According to Why haven't I earned the Guru badge? self-accepted answers don't count toward badges.
What is the reasoning behind this? On the surface it would seem to me that knowing a popular question and a good answer for it that merits 40+ votes qualifies one for a "guru" badge as much as another 40+ accepted answer.
On Mathematica.SE:
faleichik has a self answer with 100 votes
István Zachar has one with 44 votes
Leonid Shifrin has one with 42 votes
I myself have one with 40 votes.
(Several of these answers are not presently Accepted by the author.)
Why shouldn't these community-valued answers be eligible for the badge?