Tim Parks has a great piece on how the writing profession has changed in recent decades, how the market forces have altered the behavior of writers, and the importance of being grounded about one's motivations, expectations, and rewards in the writing life.
In the twentieth century people stopped just reading novels and poems and started studying them. It was a revolution. Suddenly everybody studied literature. At school it was obligatory. They did literature exams. They understood that when there are metaphors and patterns of symbolism and character development etc. then you have “literature.” They supposed that if you could analyze it, you could very probably do it yourself. Since enormous kudos was afforded to writers, and since it was now accepted that nobody needed to be tied to dull careers by such accidents of birth as class, color, sex, or even IQ, large numbers of people (myself included!) began to write. These people felt they knew what literature was and how to make it.
In the second half of the century the cost of publishing fell considerably, the number of fiction and poetry titles per annum shot up (about forty thousand fiction titles are published in the US each year), profits were squeezed, discounting was savage. A situation was soon reached where a precious few authors sold vast numbers of books while vast numbers of writers sold precious few books. Such however was the now towering and indeed international celebrity of the former that the latter threw themselves even more eagerly into the fray, partly because they needed their declining advances more often, partly in the hope of achieving such celebrity themselves.
It became clear that the task of the writer was not just to deliver a book, but to promote himself in every possible way. He launches a website, a Facebook page (I’m no exception), perhaps hires his own publicist. He attends literary festivals all over the world, for no payment. He sits on the jury for literary prizes for very little money, writes articles in return for a one-line mention of his recent publication, completes dozens of internet interviews, offers endorsements for the books of fellow writers in the hope that the compliment will be returned. It would not be hard to add to this list.