Yeah, it's like that. Lot's of people start writing, but not all of them actually finish and move on to publication. Those who continue on the journey have a lot of things pushing them forward--motivation, ambition, passion, determination, etc. All of those things come to you when you have a clear goal in mind and you really KNOW why you want to reach that goal. You could argue that the ambition and passion direct you toward your goal.
Let's make a list of reasons why you write. Everyone chime in!
Reasons We Write:To understand myself better
To share a good story
To help someone forget their troubles
To clear out the voices in my head--aka to get some sleep ;)
To make people think
To discover how the story ends or begins (the backstory)
To help me face my problems
To help the characters solve their problems
To keep from going insane!
To express myself
Because I can't NOT write
It's my passion