A method used to improve the quality of written works is peer review. This method subjects the work to scrutiny and, often, annotation or editing, by a number of the author's peers. The principle employed is that different people will see different errors, so increasing the number of people reviewing the work will increase the opportunity for errors to be found and fixed.
This tradition has long been known to the academic community, especially with scientific papers, where publication of the paper allows its quality and veracity to be criticised, the goal being to improve the quality of work.
In the field of computer software, the principle mentioned above has been stated as Linus's Law. Eric S. Raymond has also written extensively about peer review as it pertains to Open Source, in his series of papers starting with The Cathedral And The Bazaar.
Having one's work objectively criticised and improved also has the beneficial effect on many people of improving the quality of their future work.
The strength of peer review is at the very heart of Wikipedia's philosophy.