The Xbox One of course comes with a Kinect which Microsoft have been pushing since the release of the console - buyers get one packaged with their Xbox One. The Kinect not only allows you to play hands free but it is also gives users a very powerful voice command system where they can quickly use features without having to touch a button on their controller.
The only problem with voice commands as demonstrated in the video below is that it can be abused to make the console do something you may not have intentionally wanted.
The YouTube video shows below a gamer who has the username "Xbox Sign Out". He goes around trolling all sorts of players, getting in their way, attracting attention and just being annoying. When other gamers say the gamer tag they end up realising that they're Xbox is actually listening to them and is bringing them to the sign out screen.