A lot of work goes into publishing a book. Someone needs to edit the manuscript. The manuscript must be typeset and copy-edited. A cover has to be designed (most self-published books are terrible in this regard). The book needs to be marketed to readers, which can require producing ads and seeking out publicity. Paper books have to be printed, stored, shipped to distributors and bookstores, and sold; returns need to be managed. E-books have to be converted to various formats, ideally not just using automated tools.Self-published authors can try to do all of these jobs themselves. Many attempt that, and it shows. Or they can outsource some or all of the tasks. When doing so, it’s best to use professionals who have tried to publish a book before. Maybe a team that’s used to working together. Perhaps the people even sit in the same building, so that they can quickly coordinate.
Congratulations: You have just re-created publishers, but without advances.
Guan Yang, with the best response I’ve seen to Matt Yglesias’s claim, in an even-dumber-than-usual post, that publishers are useless.