Your Apple ID has been disabled

If you are seeing this in App Store,or when trying to download anything, it's most probably a billing issue, so you would need to contact Apple Care Support to have it fixed. Contact - Official Apple Support

Try resetting the account's password (and then logging out and back in everywhere) : If your Apple ID has been locked - Apple Support

If that doesn't fix it contact iTunes Support and see if they can/will re-enable it : http://www.apple.com/support/itunes/ww or https://www.apple.com/emea/support/itunes/contact.html

There isn't a way of stopping an account from becoming disabled, somebody typing in the wrong password a number of times will disable it.