I, for one, can't finish my stories.
I don't know if you guys experience this, but I have a tendency to map out a loose outline of a story in my head, work on it for a bit, and then give up and start another story.
I've finished a couple of short stories, but I never seem to have the ideas or motivation to tackle the longer ones. Any advice? :/
Well, I had a problem similar to this. But you thing was that I would be working on something, then have different a different idea. Something useful can be to try and use a computer program where you can open multiple files. If you feel like you have to give up on one of your story ideas, then just leave that file along for a few days and work on something else. It's helped me.
Well I have one complete novel and about fifty first chapters so I totally get it. At least in my experience to really finish a book you just have to force yourself to keep writing - you're not going to be inspired all the time, but just write something regularly - even if it s.ucks and you have to go back and fix it later. Usually once you get started things will start to come smoother.