Probably bad technology detecting a change. Things like current news showing up beneath the article, which changes whenever a new article is added. I've seen this happen on quite a few large websites. It might be technologically easier to drop old articles than the amount of time to fix whatever they use to determine if a page has changed. You would think a site like CNET wouldn't have to deal with something like that, but sometimes these sites that have been around for a long time have some serious outdated tech.