Firstly, writing is an arduous craft which takes years of patient drafting and redrafting in an endless pursuit of perfection. I worry that it is too easy for new writers with potential to quickly self-publish before they are ready, or lose faith and hang up their pen and their potential with it.
I have a few issues with this statement.
Firstly, as long as there has been mass publishing, there have been hack writers churning out text for profit. Dime store novels never existed to pursue perfection, they existed to sell stories and make the publishers money. To presume that all writing is literary, or should be literary, is myopic at best. Publishers are about profit, writers are about storytelling, readers are about entertainment, critics are about criticizing, and the pure art theorists are about perfection. Guess which group represents the small sales market.
Secondly, every writer has a deadline. Even famous, multi-zillion dollar writers have deadlines. The pursuit of perfection cannot be endless. At some point, every writer needs to call a spade and spade and move on. Perfection is an illusion made up by the Literati in their own myth for their own reasons, whatever they might be.
Thirdly, writing is not necessarily arduous because all writing isn't necessarily arduous. Writing a comedy story ranks as one of my favorite things to do. When one of those wants to get written, by God, I can't type fast enough.
Fourthly, writers don't self publish before they are ready, they self-publish before you think that they are ready. There is no such thing as "ready" in the market, there is only the degree to which the work is sellable. To a major publisher, a one thousand sales novel is not publishable, but in the indie market, that's good money. Once an indie writer adds up many small sellers, none of which are worth publishing by the Big 5, they can realize a nice income. Even truly awful writing, with no redeeming value, can sell if it serves an under served area of the market. "Ready" is the language of gate keepers. "Ready" means that you need somebody else's permission. I don't know a writer that like the idea of somebody's else's permission.
Fifthly, as for hanging up their pens, writers lose faith with the existing system, which relegates the vast majority of writers to no deals. Even mid list writers, who have shown that they certainly are ready, get dropped for poor sales. These writers didn't suddenly become not publishable, they simply were not profitable enough. Many more writers, of able skills, can't get in the doors, not because they aren't good enough, but because there are a finite number of books published in any single year, and publishers are interested in those books with the greatest potential return on investment.
There's really only one criteria in writing: do you or don't you entertain your intended audience? If the answer is yes, then nothing else matters.