Twitter does not allow you to follow an infinite number of Tweeps, people who have Twitter accounts. So you should regularly use a service like http://untweeps.com/ to eliminate inactive Twitter accounts you are following.
Those you can follow are a limited resource. Find the ones who aren’t tweeting anymore. http://t.co/1S5UpHvwli
— Ayman Hossam Fadel (@aymanfadel) December 1, 2014