Well the writer has had a number of books published which appear to have been successful. So he has found a market and delivered completed work.

So it's okay he's a bad writer? Sales above all?

It's more completing book length works that are published by a publishing house. Therefore subjected to content editing, copy editing and finding an audience. Quite a complex multi-stage process.

What criteria are you using to evaluate writing? Can you point to an example that you think is good writing?

(I say all this as someone who is still working on stringing words into sentences)