Off the Cup
I spend a lot of time just keeping current on web development technology. Seems that hardly a month goes by when the industry introduces something new and disruptive or when it declares something else obsolete.
If I built a website for you in the past six years, I deployed it using a content management system, which is fancy term for website software. Like most of the other software on your computer, the makers typically issue updates to fix bugs, enhance security, and/or add features. This is no different from your website. When you don't install the latest updates in a timely fashion, you run the risk of failures or security breaches. Like any living thing, if you don't take care of it, it will get sick.
The latest versions of Joomla and Wordpress have built in auto-updating features. You only need to log into the admin interface, and the software will tell you about available updates and ask if you would like to install them. If your installation does not have this feature, like Wordpress version 2 or lower or Joomla version 1.5 or lower, I strongly recommend upgrading to the latest versions.
Give me a call if you think this applies to you.