What is the theme in On Writing: A Memoir of the Craft by Stephen King?

Stephen King feels that if an aspiring writer sits down to write a story with the hopes of making money, he should quit before he has begun. Stephen King admits that there are writers out there who do it for the money, but feels that these writers are not good writers. These writers review theater or sports for the local papers. These writers butcher words and miss the meaning of symbolism and theme.