Twitter hopes to combat spam and bot accounts by limiting the amount of users you can follow in a day. It’s now down from 1,000 to 400. Admittedly for us, that’s still a whole lot of accounts to follow in a 24-hour period. "As a part of our commitment to building a healthy service, we remain focused on stopping spam and abuse on Twitter," a spokesperson for Twitter told Engadget. "We found that having a high daily follow rate contributed to follower churn, and as a result, we are reducing the daily follow rate limit from 1,000 to 400."
Follower churn is described as the process of following and unfollowing accounts. It’s done to get a users’ attention and try to get others to follow back and increase follower count.