WordPress sites need to be hardened to prevent attack, which means that best practices should be followed in maintaining the website and locking it down. As an open source platform, the main software that runs WordPress is always being updated when vulnerabilities are discovered. That means, the software needs to be updated to the latest versions. Plug-ins are additional software programs that add functionality to the main WordPress website. They also have frequent updates which are needed for security of the website. Updates are frequently missed in the shared hosting solution due to lack of diligence or knowledge of the user.
There are 2 potential solutions to this, VPS Hosting (Virtual Private Server) and Dedicated Hosting. VPS Hosting is advantageous to Shared Hosting, because you have control of the server and what resources will be provided. You can set the size of memory and use of resources for each account. Although the websites are still sharing the same server, they can be configured for security and best use. This is a great solution for businesses that are small to medium in size without heavy user traffic. A website with a great deal of traffic will require a Dedicated Server where the website has its own server and resources.