Writing isn't generally a lucrative source of income; only a few, exceptional writers reach the income levels associated with the best-sellers. Rather, most of us write because we can make a modest living, or even supplement our day jobs, doing something about which we feel passionately. Even at the worst of times, when nothing goes right, when the prose is clumsy and the ideas feel stale, at least we're doing something that we genuinely love. There's no other reason to work this hard, except that love.