WordPress security is an important consideration. It's a fair criticism of WordPress to say that the platform does allow, in some configurations, a hacker to gain access to your site. Generally, WordPress's security depends on the user keeping core files and plugin files updated.

Wordfence doesn't replace a user's responsibility to keep WordPress updated and secure, but offers additional layers of protection. It's very broadly featured, with dozens of available security settings, everything from scanning core files for changes, to blocking individual countries. The free version is certainly worthwhile, while the paid version adds additional layers of protection. There are a lot of settings here—and that's a good thing—but it will take some time to get it set up correctly.