... if I wanted to spend my time marketing my books I'd have gone into marketing. I'm a writer. Every hour spent on marketing activities is an hour spent not writing. Ditto editing, proofreading, commissioning cover art, and so on. This is what I have publishers for. It's called "division of labour", and it's why self-publishing — unless you're an instinctive sales/marketing genius — is a Really Bad Idea™ for most writers.
I was faced with this exact problem when I kicked off my self-pub venture. I could leave the marketing to someone else and concentrate on writing, or I could do it all.
I ended up doing it all, for one simple reason: from everything I've seen, the stuff I'm producing isn't easily marketed to big swaths of people. It's a niche of a niche, and for that reason I took it upon myself to get it out to the few people I felt would respond most to it. The best way to do that, I thought, was to go and sell to them face-to-face.
Yes, this system has tons of downsides, not the least of which is that it's time-consuming and exhausting. Yes, I do not recommend it to everyone. No, I do not regret doing it for a second, because while I may have a tiny fanbase, they're almost all people I can call by their first names, and I'm not sure I could develop that kind of thing if I went through a conventional up-market publisher.
I'm a writer first and not a marketer, but the more I think about it, every writer needs to have at least some facility in selling their work to an audience. I don't think I'm a marketing genius — if I was, I'd be working in marketing — but I think I know my stuff well enough to be able to pitch it succinctly to the people that matter.
I don't know if it'll be like this in another five years. I'm wildly curious to find out, though.