Simple English~

Everything is Fair in this World?
Ironically, We can't gain the same amount of harvest although
we put our greatest Efforts at the same time
For Example, 2 buddies are study at the same institution,
they attend the class together;
they study together;
they play together;
they learnt together;
they put the same efforts for their exam;
but ...one of them able to graduate with distinction and have the chance to study abroad;
and another one only can graduate with pass.
why? what the hell is going on?
In this case, Why we still gotta do our best?
What is the reason we pay for it?
Who can tell me the answer?
you? God? maybe, who know?