Spam problem on Web 2.0 sites like Facebook, LinkedIn and Twitter is tiny compared to email. Spammers are looking for new ways to spread their messages, and get them in front of potential audience and victims. Spam is getting harder for the email spammers because anti-spam companies are stopping most of the spam. People are used to receiving spam in their email inbox, but when you get a spam on a site, a site which is all about community and bringing people together do you delete it as hastily?”]
Source: https://grahamcluley.com/twitter-admits-it-has-a-spam-problem/