When you have the Status window selected and issue the mode command without specifying a target, the target defaults to Status and is issued to the server. If there is a user with the nick Status the mode command might apply to him, even though that definitely wasn't intended by the issuer of the mode command.
It might only effectively change the mode of the inadvertently targeted user if the issuer of the mode command has rights to perform such action. (fe. if the issuer is an ircop or the server restrictions are lower)
This might affect other commands as well.