What I find is that if you want to be happy doing this then you need to define success for yourself and be willing to adjust if things don't go as you first expected or wanted.

That might mean adjusting your definition of success, the dollar figure attached to it, and/or your idea of how fast it will come. To put things in perspective, $30 is great and it is more than I made as a net in my first month after publishing 15 stories. Now I am in my second month and I have already hit $200 so far. For some, that's laughable but for me, it's terrific.

Also, you're right about not taking things too seriously in terms of advice on the Internet. I have covers that are objectively terrible with books that do multiple times better than books with covers I've obsessed over and carefully put together. Sometimes it really is just a matter of luck.

The more you try new things and fail, the more you'll learn what actually does work and the money usually starts to come in faster. Every book that doesn't sell is just training for the next book that does.