Terminate inactive websites

There are literally thousands of websites, many of which are no longer maintained and/or used. I would recommend terminating websites that have been inactive for more than 18 months, either have not been updated or have not be used/viewed. If no one is updating or looking at the site in over a year, it clearly has outlived its usefulness. It also poses a security threat. If no one is monitoring the site, someone may be using it for unauthorized activities.