Reward for Mitzvah, why it doesn’t happen.
-This means, as a general rule it will happen, however there are exceptions.
-The systems of reward and judgment are very complex, there are many different factors.
-If everything is in place it will happen, this is normally the case.
-There are also many levels in doing something, this includes effort and how a person does a deed.
-Do not wonder if someone does a mitzvah but does not receive the reward.
-However even if one does not get the prescribed reward, the deed does not go to waste, it will still serve him in time of need.
-(Medrish Talpiyot- Ot-Alef)