I got some private messages and want to talk about my definition of quality.
When I talk about quality I don't mean just the interior of the book, the formating, description, cover etc.
An example: For me quality begins with the right choice of the penname. Let's say I want to publish a book about superfoods. I would take a female author because women are caring more about their health than men (just my opinion). Superfood is a very modern topic. That's the reason why I would choose a modern name. I think 28 is a good age for my autbor (young enough, modern, creative but also old enough to perceived as an authority). Then I would choose a good profile pic for my author. She has to look healthy without make-up. If she looks to good I would put some redness on her skin with photoshop. If the pic looks too professional I would use a blur filter, reduce the color saturation etc. Maybe I would add a date 11-2-2017 to the pic (so it seems to have been taken with an digital camera). At the end I would write the biography. EVERY sentence must have a reason! Eg. I would never choose a random hometown for my author. I would search on the Internet which cities/regions are well known for health (or where you have a lot of nature). And so on...
As you can see, everything I do has a reason. I don't create the things separately (profile pic, cover, description, title etc.) For example: If I have set up my author profile and want to create the cover ....let's say most of my competitors in my superfood niche has a "superman sign" on the cover ...I would never use it because it would not match with the personality of my author. Or let's say "Superfood Kickstart" is a great keyword ...I would not use it in my title. Another example: I'm able to create an extremely professional and premium looking book cover, very clean, high glossy, maybe with mirror effects etc. ...but it makes no sense if my author is a lovely looking young woman who lives in the nature and loves to catch butterflies in her free time. xd
Everything you do must have a reason. And everything must fit together to produce a "round" image at the end - This is quality for me. Everything else is generic but Uniqueness is what sells.
It's really hard to explain but look at your book from the outside and see the whole image. Don't look at your title and think: "Okay, I have to write keyword 1, 2, 3, 4, 5, 6 in my title, because the more keywords I have, the higher is my visibility, the more I'll sell." Nothing against keyword optimisation but if your title looks like spam you destroy your whole image. Then your author profile looks like fake for the customers etc. You have to create everything with very much sensivity (and not just with the dollars in your eyes).