Conflict

The most important element of a story is conflict.
Every Story must have a central conflict.
The conflict must be relevent to the audience.

The audience experience the story with emotions of the protagonist trying to solve the conflict.

Conflict
Two people want the same thing and want it very badly, but only one can have it.

The protagonist is trying to get what he wants and prevent the other from getting it. The conflict is a real do-or-die, I can't go on living if I can't have you is a conflict.
Achieving the thing should be very difficult, but not impossible.

The story should always focus on the main conflict.

The story shouldn't way off into side-stories unless they directly relate to the central conflict.

The central conflict should be the most important event in the characters lives, and maybe the most important event in the the world. Finally the hero will face conflict in a final crisis and win or loose.