As a director you are ultimately responsible for the look and feel of the film, without vision and knowledge of the codes and conventions of genres, then it's really hard to amuse an audience with what they see on screen. Without passion you will loose the motivation and respect from your crew causing the production of your vision to collapse. I find these two words very crucial to a director because directors have to know what they want and love what they are doing.
There are two specific types of directors. Those who take on screenplays using their vision to interpret how it should look and those who write and direct their own stories. Writer-directors are really the auteur's of the film world in the way that the story starts in their head and ends up on the big screen, showing how they feel "their" story should be told.
All you have to do is find out which one suits you, not everyone can write an original screenplay but not everyone can guide a film crew. People like Steven Spielberg started of like us, he was just given the chance and his work improved over time. Check out the other Topics to find ways of improving your skills.
