Don’t know if this is intended or not, but when you take your skills while leveling and do not change them you have more than 20 specialization points:
Never really realized it until I despecialized to respec something.
After doing that you basically miss 1, 2 or 3 points, depending when you took the specialization.
(My Manastrike, the first skill I ever specialized and didnt change until today, had 23 points without me even realizing it until now).
I am guessing the third skill to specialize had 21, but I already respecced it a while ago.