Twitter will start deleting accounts inactive for more than six months, unless a login is made before the deadline for deletion, scheduled for December 11th: inactivity, for Twitter, is determined based on login. , not upon publication.
Twitter said the decision was made because users who haven't logged in for so long have been unable to accept updates regarding their privacy policies. Deletion will also improve social credibility because inactive accounts will be removed from people's follower counts.
Update: Twitter has changed their mind.
