If you're 100% sure you're not going to expand your website in the future, there's no need to invent a new bicycle — WordPress had proved to be famous, convenient, easy, beginner-friendly. Well, I personally use it now for all my projects. It's like old comfortable pajamas: you've tried other silk and classy nightgowns, but you always come back to your plush 3 times bigger panties.
It's the easiest CMS, be sure you won't need to ask techies to help you with anything. WordPress simplified everything that should be simplified, and for extra options they are constantly developing great addons and extensions. Really, I can't imagine anything you can't add to your WordPress with the help of extensions, they have them for everything you can imagine.
But as I said, WordPress is rarely used for big websites, since with a growth of content and audience a WordPress website can lose the loading time. Nobody likes slow sites. And it's well knows, WP has security issues. I know the team improve it with every new update, but doubts still exist.