Why are video games bad

Video games themselves are not bad unless you are referring to violence or inappropriate messages which, in more recent video games, has become more prevalent. Some games are good for people to play. The Wii has made generous contributions to a healthy gaming experience through its interactive interface.
I guess the only reason I can think of as to why video games would be bad is the potential activities that the user is missing while they are playing video games. As long as the user is active outside of their playing time and maintains a healthy lifestyle outside of video games it is a healthy hobby.
A recent study which can be found on numerous websites and magazines says that video games increase the user's dexterity and concentration and that they usually score higher on visual tests and attention to detail. Here's a link.

http://www.guardian.co.uk/technology/2009/feb/12/computer-games-eu-study