Yes, there is one. To give you the short answer: Quality, and the lack of quality.
The person who appears to have the scoop on it is here: The Self Publishing Review
The first thing he comments on is Quality of grammar and punctuation.
The second is poor quality writing.
Here's a quote:
"This sort of overwriting is neither literary nor clever: it's just overdone (and bear in mind here that literary fiction is my genre-of-choice: I am not unaware of its conventions or standards). _____'s writing is far too complicated, and he often favours that complication over clarity and meaning. The text is thick with clever-sounding phrases, many of which make little sense; and I found a lot of clichés buried in his overdone language."
When I look at this very closely – I see the blogger is British – note the 'u' in favours. This would indicate that he is also reviewing British authors.
According to his bio he is more than qualified to judge – "I've worked in publishing for over twenty years, as a writer, a researcher and an editor." According to his rules, he stops reading at 15 errors. One book rated 55 pages. Six books bombed out at 3 pages. The majority bomb out by page 11. He appears to be fair, often he sounds wistful that a book didn't do better.
I believe he has a point – quality is everything – and anyone 'Going DYI' has to have a copy editor.
Max Dunbar over at 3 a.m. magazine thinks the whole song and dance about "Independent Publishing" is – well – sour grapes by folks who can't be published any other way. (Would anybody turn down a nice hefty advance and a 3-book contract?)
He does make a good point that the line between (hiss) 'vanity' publishing and (oh baby) 'self' publishing is blurred – with more companies opening up to blur the lines all the time. Even Harlequin Romance as a vanity-publishing arm – and a digital publishing arm – and an editing service – and…
People are making all kinds of money – though usually not the authors.
So muddy are the waters that he sites this example: "The best example of this scam is the YouWriteOn debacle of this year and last. YouWriteOn is a writers' message board, or 'community', whose admins announced in the autumn of 2008 that they would publish 5,000 books, for nothing, by Christmas." Eventually less than 300 novels were distributed – after the author paid a fee. (Fee = Free?)
Yet, there is Year Zero.
Dan has published his own statistics – er can't find the link – showing us his book sales as an Indie author. Yet, an argument could be made that Year Zero isn't self-publishing because there is more than one person doing the writing. To me that would fall into the co-op or micro-publisher category.
Ah! Here is Dan's link: The Man Who Painted Agnieszkas Shoes As you can see, there weren't that many books sold, but there were over 220 copies downloaded.
It appears that an author on the verge of Self-publishing should invest in a editor.