One way to think of this concept is to imagine a conversation. You'll make reference to previous conversations, call upon knowledge shared by the participants, make new points that advances the conversation. Each academic discipline has different ways of handling the mechanics of citation because each treats knowledge a little bit differently and each has a long history. It's the polite thing to do. Some were born to write, others were born to do anything but write.
Writing is a learned craft.
It's frustrating in that way-your ultimate goal is always slightly out of reach. But it is also incredibly rewarding to see improvement, to reach that reader, to make connections. The rewriting part is most important here. Instead, of spilling out those perfect first drafts, strong writers know that they will need to revise again and again. We write in order to figure out what it is we want to say.