see -
Halcyon&on's thesis =)
This is something that can easily happen to someone in science (and probably other disciplines, although I have no experience) where one learns and studies and focuses on one topic. Eventually one becomes the world expert on a topic so narrow that nobody else cares about it. At this point, some journals may still publish your work, but very few people will take the time to read it. Hence, your life becomes an excercise in intellectual masturbation.
This is why it is good to collaborate, to go to meetings, to diversify one's interests. Intellectual promiscuity is like linking your nodes, it benefits you and it helps the system.
Of course, the flipside is that something obscure and irrelevant you're studying today may somehow be crucial twenty years into the future. That's what makes science so much fun ...