Forging Ahead in February

I took the plunge and sent an (extensively revised) article about Crater Lake to a children's magazine, also sent the revised picture book about Our Lady of Guadalupe to a Catholic publisher. Submitted a short poem ("Ode to Menopause") to a humorous poetry contest, too. Will I get rejections in March/April? Could be. Meanwhile, working on other projects.

Writing a novel is like driving a car at night. You can only see as far as your headlights, but you can make the whole trip that way.
– E. L. Doctorow

A Mystery of My Writing Life

Whenever I'm the most excited and think that a manuscript is great and ready to go, it still needs a lot of work. Whenever I'm hesitant and unsure that the manuscript will appeal to anyone, it's deemed good (and sometimes published). Something similar happened frequently when I took exams in school. When I thought I aced it, I got only an average grade. When I thought I bombed, I did well or at least much better than I expected.

Can anyone explain this to me?  I'm confused...