Yes, it is called Amazon Digital Services. It is where authors publish manuscripts that have been rejected by publishers, or which they have rejected themselves by not bothering to submit.
Writing is a craft and publishing is a commercial enterprise. Like other enterprises that depend on appealing to the taste of consumers, such as movies or fashion houses, or cell phone makers, it is not an exact science, but companies in these spaces do know an awful lot about what works and what doesn't. It does not mean they don't make mistakes and produce dreadful duds from time to time, nor does it mean they always know when they have a best seller on their hands, but it does mean that they know a non-starter when they see one, at least 99.99 percent of the time.
Writing is a craft and can be studied as a craft. Publishing is a business and can be studied as a business. Both the craft and the business are written about extensively. They are also both reasonably transparent so you can study them for yourself. To be certain, there are charlatans peddling bad advice, as there are in any trade, and sometimes the advice of the charlatans (promising as it does an easy road to riches) can become popular and even be received as gospel. But those who are serious about the craft and the business will not be fooled for long.
Like all industries that appeal to taste, there is the je ne se quois factor on top of the craft, and that makes some people sneer at the whole idea of craft. But the je ne se quois factor really is the icing on the cake. You may not succeed without it, and you may not be able to learn it if you don't have it, but it can only successfully operate on a sound base of craft.
Read the vast majority of self published works (or join a critique group and read people's submissions) and what you will find in almost all of it is a basic deficit of craft.
If the craft was remedied, would they become best sellers? Probably not. Even with the craft remedied, most would lack the je ne se quois factor. But in many ways there is nothing that highlights the vital role of craft then reading works where it is so obviously deficient.