Novelists need a lot of things to write well. They need some talent with language and story. They need to have read a lot to learn the structures of fiction. They need to study and understand all the elements of craft-- like characterization, plot, setting, language, show and tell, voice, POV and on and on. They need practice, lots and lots of practice. BUT the number one thing they need, in my humble opinion, is a passion for writing. They don't have to love to write all the time--good god no-- but they need to be passionate about their writing. And here's why--the writers who end up publishing and making a life, whether it pays all the bills or not, out of writing are those who continue to write and try all kinds of ways to get better.
I fully admit I have a love/hate relationship with writing. I love it much more than hate it but there are a few frustrating moments when I do hate it. But I am always passionate about it and it is this passion for writing (not publishing which is a different beast all together) that sustains me. I've met a lot of talented writers, particularly in graduate school (MFA in Writing, yep) who are not writing now and have published very little. The praise a person gets in school isn't going to sustain him/her as a writer once out and the teacher and student audience is gone and the larger one not yet materialized. What sustains a writer is that passion, that learned love of the act of writing. Honestly, it takes most writers years and years to start writing well. What you have to do as a new writer is just keep writing and finishing (VERY important to your development is finishing work so you know what it's like to write an ending) your manuscripts. If you focus on what you love, write what you love, then you will feed that thing that I think is most important--a passion for writing, which means you will do it whether you get the pay or praise of the outside world.
Novelists do need many things (including luck) to get published but what sustains writers, I think, what keeps them going and writing the next manuscript and the next is passion. A little talent and a lot of passion will push a writer to keep writing and learning and those things make many things possible. You have to write and finish work to give yourself a chance to write something you've always wanted to write. The passion keeps you writing and the writing, finishing work, gives you hope and that's a fundamental part of the writing life.
Or so I think today.