It's when you haven't video chatted for A LONG TIME, because you either:
a. Broke your web camera, so you can't video chat anymore.
b. You have no one to video chat with.
c. YOU DON'T HAVE A CAMERA TO BEGIN WITH!
friend: dude, i have been in video-chat coma for like a month!
you: what, why?
friend: because i have no one to video-chat with!