Authors should enjoy what they're crafting with words. If you aren't, then how will your reader love it and fall deep into the book's world.
Find an idea that keeps you up late at night because you can't stop thinking about it. That is when you know you can and will write a winner. Like my WIP and the idea for my future project, I am overjoyed to write them. They've caused many a sleepless night for me. Even though I'd rather have been asleep dreaming of chipmunks and faeries, it was a delight to get to know my characters, setting, and plot instead.
So, make sure you love what you're writing. If not, think of something else and fast. Why waste time on something that isn't making you smile and jump for joy?
What are your thoughts on this subject? Have you ever had to stop a project because you weren't feeling it? How have you felt when you absolutely adored your story?