There are so many nuances to writing a successful novel, so many ways things can go wrong. It is actually inconceivable to someone who isn't a veteran of the ms wars, who hasn't been at it for years and years, who hasn't made all the mistakes, who hasn't reached that point when their writer group earnestly believes the ms child they helped to raise is clean and spiffy, and then sadly, discovered many rejections later that the child needs a year or two more of prep. When will it ever end?
You have to be patient, but you can't be patient unless and until you know just how patient you must be, and that requires a realistic knowledge of precisely what is required of you, what it takes on every level to write a successful novel your market will embrace, regardless of genre.
And btw, don't set arbitrary deadlines for completion of the novel, or any part. Just stick to a schedule, and let it come in due course.