No one can guarantee that your website will never experience a hack or infection. This is partly due to the various factors and techniques that come together. Every new update to the WordPress core, theme or plugin may contain new security vulnerabilities. This may also have to do with the way in which the customer keeps his data, how the website is structured or what security measures the hosting provider implements.
When your website is hacked, I immediately start working on identifying harmful files and find out the cause. With the full-service package I make a daily safe backup of your website on an off-site server, in which case your data will never be lost and I can easily roll back a version.
My basic security measures include configuring a free WordPress security plugin to receive attacks and security issues in my mail and setting up a Firewall, running a malware scan and deleting malicious files, actively tracking unsupported plugins and themes, as well as ongoing recommendations and advice on security best practices to keep your site safe.
With the full-service package I perform the above actively and monthly. With the basic package I can execute it on request and the hours are paid with my regular hourly rate.