It is the difference between having ideas and then having the patience, the dedication (as Cia said), and the willingness to make them happen.
Stephen King says that "Talent is cheaper than table salt. What separates the talented individual from the successful one is lot of hard work."
And he's right. Lots of people have the ideas to write, less are willing to put in the time and effort. And yes, you will need to sacrifice other stuff you want, other things you do and the time you spend on them if you want to do it, and then do it well.