In case you don't know exactly why and when you should switch to the latest version of Joomla, then you should know that your site would be more vulnerable against cyber-attacks if you don't update to the newest version of Joomla. Today, if site owners don't upgrade their website regularly, whether they are static or not, can be hacked by professional hackers.
Joomla is considered as an open-source platform where websites and applications can be created and enhanced easily. It is known as the content management system (CMS) that would be able to connect your site to MySQL. This is done to make content management and delivery easier for managers and visitors.