This can be easily avoided
Infected code is loaded onto computers from the internet via the web browser, often unknown to the user, when they visit an infected website. These malware programs change browser settings, alter system files and create new default webpages. Typically, malware collects personal information or renders computer unusable. Several malware programs even regularly update their own program codes on infected more users.
Make sure your site does not became one of these sources for your customers, like these examples.