In order to get the optimal outcome for your website over time, the best practice is to purchase a monthly, fortnightly or weekly maintenance package alongside your website build, for the purpose of keeping your website and software infrastructure working, up-to-date and growing.
In addition to this, it is recommended that you manually test and check your website often.
This may include adding new articles and information to your website, updating old information that may have changed over time, and periodically checking links, content and website support such as Google integration and statistics to ensure everything you purchased is working as desired and an appropriate amount of traffic is flowing through your website.
Your website is a tool for your business. Like any tool, if you take care of it, it will serve you well.