Twitter considers 10,000 character limit

Why might this be a bad idea?

http://recode.net/2016/01/05/twitter-considering-10000-character-limit-for-tweets/?utm_source=Daily+Lab+email+list&utm_campaign=456e06ed81-dailylabemail3&utm_medium=email&utm_term=0_d68264fd5e-456e06ed81-380333213

http://www.theguardian.com/technology/2016/jan/05/twitter-shares-plummet-rumor-10000-character-tweets-jack-dorsey?utm_source=Daily+Lab+email+list&utm_campaign=456e06ed81-dailylabemail3&utm_medium=email&utm_term=0_d68264fd5e-456e06ed81-380333213