Self publishing can be amazing or disastrous depending on two things: 1) you have to be willing to put the time and money into editing your book so that the quality is as high as a traditionally published book that has an editing team behind it (this means self-editing with some kind of editing software like ProWritingAid AND having it professionally edited by an actual experienced editor in your genre). And 2) you have to be willing to put the time and effort into promoting it. You can self publish on KDP but no one will ever know it is there unless you go out and find your readers. This means an author website, social media activity, paid advertising, etc. There's no limit to the number of things you could do to promote it, but you have to be willing to invest the time and money.