Write with purpose
Science-fiction writer and programmer qntm about writing:
Write with purpose. Do not write just because. Don't write because you love writing, because you love reading your own writing, because you love other people reading your writing or because you love feedback. Instead, write because you have an objective. Your text is supposed to achieve something. Write because you want your writing to accomplish something, because you want your writing to have an effect on the reader.
In fact, flip those two things around in the phrase, in order to make the emphasis clearer: first, develop an objective. Discover that there is a story you want to tell, a particular piece of information you need to share, an emotional instant that you want others to experience, a particular reference work missing from the world. Second, in order to accomplish that objective, write.
(According to Wikipedia, qntm is the pseudonym of British author Sam Hughes.)