The choice of website you will require really comes down to your needs. If you want to sell products, run a blog, add regular content or would like to run a newsletter system through your website than you will need a CMS system. If however you want a website and only intend to make occasional edits then a static website might be a good choice to make.
So you might be wondering what a CMS system is. A CMS system is a content management system. They are database driven websites and the two most popular are known as wordpress and joomla. With a CMS system you can add your own webpages, products and make edits as needed.
A static website is designed purely with HTML code and does not use a database. Therefore edits can only be made by someone familiar with HTML. They are however cheaper to run, require very little maintenance and are super fast as they have no database slowing them down.
A CMS system such as joomla needs to be maintained. The database that gives you all the awesome functionality of making edits needs to be kept updated. Like a desktop system or android device joomla will release performance and security updates to keep your site running smoothly and securely. The same goes for the plugins and modules that run on the backend of the website. Either yourself or your designer will need to make these updates on a regular basis.
The CMS system also takes up more disc space and requires more bandwidth therefore you can expect to pay a little more on your annual hosting costs.
The static HTML website lacks a database therefore there is no need for constant maintenance. Its faster then a CMS system even on lesser hosting. The users browser uploads the code directly from the HTML page but a CMS system such as joomla requires the browser to request the information from the database resulting in the HTML site displaying much faster. In the modern world where we have more and more people using mobile devices this should not be underestimated. If your working to a budget and don't intend on making a whole host of changes then a HTML website is a really solid option.
Reading the article it might come across as I am favouring a HTML website over a CMS System. Its not really the case though I really love joomla its my go to website and I can't speak highly enough of it. However I want to give people a good option on a cheaper alternative that can serve a purpose. A lot of designers are overly dependant on wordpress in fact a lot web design companies don't even know how to code. They rely 100% on editing wordpress themes therefore it is pushed on clients as the gold standard of website options which it most definitly is not.