It occurs when the most high value contributors to a community realize that the community is no longer serving their needs any more and so therefore, leave. When that happens, it drops the general quality of the community down such that the next most high value contributors now find the community underwhelming.
While continuing glitch explorations, I will also be starting a series of typographic discoveries involving phrases I have heard over the past 8 months. Also, a series of typographic interpretations based on The Terror, an album that I find to be very emotionally close. Stay tuned.