► Subscribe to the Financial Times on YouTube: http://bit.ly/FTimeSubs<br /><br />FT columnist Lucy Kellaway says chief executives need to have a hard think before deciding to join Twitter. She looks at the successes and failures of CEO tweeters including Tim Cook, Marissa Mayer, Elon Musk and Warren Buffett.<br /><br />For more video content from the Financial Times, visit http://www.FT.com/video<br /><br /><br />Twitter https://twitter.com/ftvideo<br />Facebook https://www.facebook.com/financialtimes
