How can writers create quality fiction?

I would like to exchange ideas concerning fiction writing for self-publishing purposes. There are multiple platforms to self-publish a novel, novella, or short story. I do not believe the platform is relevant to the content. The content of the eBook must attract the attention and interest of the reader regardless of platform. My fictional writing relates to the fantasy or apocalypse genres and often combines the two. Countless resources and advice exist for use in perfecting grammar, spelling, editing, structure, and formatting. These are the framework. A quality eBook of any length will have the correct framework. I do not feel there is really any excuse for a writer, self-published or not, to have mistakes in the structure of their eBook. Grammar, spelling, and formatting errors are not acceptable. A self-published eBook containing such errors shows laziness or an inability to use available resources on the part of the author. The framework and structure of the content should be satisfactory so I do not believe such aspects of writing are a variable separating poor, mediocre, and exceptional work as every author should be equal in that sense. The difficult aspect of writing fiction is creating characters and a story to engage a reader. The pinnacle of fiction writing is the ability to prompt real emotions on the part of the reader as a reaction to the characters and story conveyed to them. This is by far the most difficult aspect as well. Other writers can only provide a limited amount of help and advice in achieving a story to capture hearts of the readers. A book can be written perfectly with every relevant detail included, a well-defined plot with no in-discrepancies, and a carefully constructed story line, yet it can easily fail to provoke any reaction from the reader. It requires a talent of a different caliber to write fiction the reader will care for. What can aspiring authors do to improve this talent in themselves? Is it a talent that can be improved or developed or do some authors possess it naturally? I am asking such a question because I can easily see this ability in the works of other authors and it is immediately apparent whether the author possesses such a talent or not. I am not entirely sure if such an ability can be learned, as some authors write prolifically and are obviously trying very hard, but they never achieve this factor. They write and publish and try over and over but never create anything that is not immediately forgettable. What are some of your thoughts on this topic?