Book publishers generally focus on two areas: influence and money. While different publishers have different missions, generally they want to produce good books that entertain and inspire people and help them think critically about their world. Publishers also want to make money. Without it, they cannot keep their doors open. And publishers deserve to make a good return on their investment, because they are the ones taking the main financial risk.
Christian publishers also seek to build Christ’s kingdom by equipping readers intellectually and practically to apply the Bible’s timeless truths to contemporary issues and trends.
To meet these goals, each publishing house is looking for several things: a good idea that fits its philosophy, target audience, timeliness, evidence of good writing, and a good platform. If you cannot demonstrate all of them, chances are your book will be rejected. If you can, however, you will likely have your pick of publishers. They are, after all, in the business not of rejecting manuscripts, but of publishing them.
To that end, publishers sift through the mountains of proposals and manuscripts they receive, choose those that best fit their philosophy and seem financially feasible, pay the authors (and, by extension, the agents), edit the books, provide covers and other editorial services, and promote the books. They receive a return on their investment through the sale of the books.