[witoldc]

All of these online communities face the same problem:

As they get bigger, the quality of the membership becomes severely diluted. Eventually, the crud fills the pages, the 'good' members leave, and all that remains is the crud.

This is happening on Quora too. Look at up-voted answers on non-tech questions. All it takes is a bunch of nicely formatted paragraphs, lists, bolded text, and a bunch of nice pictures. Tons of posters are commenting on places they have never visited and things they know nothing about.