There comes a point in every writer's career when they need to start making decisions about what their writing means to them. They need to examine their goals and strategize on how to get there.
For many writers, there is a shift in mindset, where writing moves from being a hobby to being a business.
Before I go much further, I do need to stress that there is nothing wrong with writing as a hobby. I know of a few hobby writers, and they are extremely knowledgeable about the craft. However, if you are looking at publication with the intent to sell your books (and I do mean books plural), then you have migrated past being a hobbyist and into the realm of running a writing business. Exactly how that business looks will depend entirely on your goals and ambitions.
This decision about making writing into a business can come very early within a writer's career, and it should. It doesn't mean that it has to suck all the fun out of writing your stories, but it will help you focus your activities, hopefully becoming more productive and working towards your goals.
So, let's take a look at what writing as a business really means.