Ujm
Each person gets rewards in the true world above only on the level of what is EXPECTED on his level of frumkeit from the way he grew up to his surroundings etc…..
Hashem doesn’t say you weren’t a tzaddik like Harav Chaim Kanievsky ZTL so you get no reward at all cause You weren’t expected to be such a tzaddik during your entire life only the exact level Hashem made you like. And that’s what we are all responsible for as parents and rabbonim etc…. Each according to their level exactly is what they get rewarded for upstairs and what they are held responsible for on their level.