So an old marketing adage, that has proven to be true over and over, is that incentives govern behavior. Every. Single. Time. This applies to individuals, groups, companies, governments, and more. Whether we think about it or not, this is true. Ultimately why we do things answers, "What's in it for me?"
Rand Fishkin, friend and a great businessperson, says this: "to act ethically, the best things to do is set up your life, your company, and your career so there is as little incentive as possible to act unethically." Because, odds are, if there is nothing in it for you, you won't do it. For writers, this applies to two things: your writing, and how you market to and reach readers.
The first is simple: if you are not writing, the reason is usually because you have not set yourself up with the right incentives to do so. Alternatively, you have a greater incentive NOT to write than to write. The reason often relates to fear. Writing is scary, you might fail. You don't want to fail, so you don't sit down and write. The opposite incentive works, but is harder to hang on to: you could be wildly successful as well. But there are other reasons to write. You just need the one that works best for you while defeating or simply facing your fears.
This is the reason your "why" is so important.
When you are reaching readers, you must give them a reason to do things like buy directly from your website rather than going to Amazon, and that must go beyond price. You must provide them with incentives, and often those incentives involve connecting with you. You must make that connection matter to them, and that must be because it matters to you.
Or you can take other approaches, but you must have an incentive beyond monetary returns to publish your work, to market it, and to interact with your readers and make those connections. Because if you don't have an incentive, a why, you won't do it, no matter how many habits you form or how hard you try to push yourself to do it.
Because incentives determine our behavior. Every. Single. Time.