  Success of planetary-scale online collaborative platforms such as Wikipedia
is hinged on active and continued participation of its voluntary contributors.
The phenomenal success of Wikipedia as a valued multilingual source of
information is a testament to the possibilities of collective intelligence.
Specifically, the sustained and prudent contributions by the experienced
prolific editors play a crucial role to operate the platform smoothly for
decades. However, it has been brought to light that growth of Wikipedia is
stagnating in terms of the number of editors that faces steady decline over
time. This decreasing productivity and ever increasing attrition rate in both
newcomer and experienced editors is a major concern for not only the future of
this platform but also for several industry-scale information retrieval systems
such as Siri, Alexa which depend on Wikipedia as knowledge store. In this
paper, we have studied the ongoing crisis in which experienced and prolific
editors withdraw. We performed extensive analysis of the editor activities and
their language usage to identify features that can forecast prolific
Wikipedians, who are at risk of ceasing voluntary services. To the best of our
knowledge, this is the first work which proposes a scalable prediction
pipeline, towards detecting the prolific Wikipedians, who might be at a risk of
retiring from the platform and, thereby, can potentially enable moderators to
launch appropriate incentive mechanisms to retain such `would-be missing'
valued Wikipedians.
