This may seem like a baseless comparison (WordPress uses HTML after all) but when it’s your project, you should be doing all the research you can. The comparison between HTML and WordPress is valid, because a website developed with simply HTML (and no CMS like WordPress) can and will be a lot different than one developed using WordPress.
In today’s context, you’ll probably want a dynamic website capable of capturing your brand identity perfectly, giving you great SEO advantages, and fits in perfectly with your resources and goals. Skilled developers can do all that and more, WordPress or not. But on the following grounds, one or the other comes out the winner.
Take a look:
WordPress is a powerful CMS and gives you a lot of flexibility in matters of customization and development. But it also has more limitations than HTML in regards with database querying (which makes it easy to use) and native specifics/code (which runs on a simple logic of its own that must not be messed with).
For highly scalable websites that give developers complete control over every single aspect of back-end and front-end, HTML is the way to go.
That’s not to say WordPress isn’t capable of handling large traffic websites and huge amounts of database queries. It only means that in the hands of a skilled developer, an HTML website can be coded to do more within the same server capacity than a WordPress website.
WordPress is more ‘readymade’ than HTML, given that all you need to do is download the software and theme/plugins you need and set it live on the web. The admins get a nicely user-friendly admin-area (dashboard) to work through for content updates and more.
It’s easier to develop a WordPress website too, since it gives large room for flexibility and modification (and still retaining its basic structure). For example, the template hierarchy, the native APIs and their functionality, etc. make for some great tools to start with. To develop an HTML website is completely different. You have to define your own logic to be able to work with it.
Simply put: Without the semblance of “rules” to keep development in line (as is the case with HTML), the entire project can get out of hand. This is where WordPress wins.
Since WordPress is easier to develop, it requires less time and resources.
While you hire WordPress developer, you can usually get a pretty good idea about their expertise level by taking a look at the quality of projects they have made. This is actually the entire basis of huge marketplaces like Envato, where theme/plugin demos and product screenshots are usually enough to know how good (or not) the developer and their product is.
With HTML, it’s a little trickier. I have known developers who can work wonders with HTML but hit their breaks at writing CSS. Even a website with great functionality, if it looks bad, will not get many eyeballs (exception being hugely popular ones like Google).
Essentially, within the constraints of a limited budget and timeframe, a WordPress developer can do a much better job at building a beautiful and efficient website than an HTML developer, given their skill levels are about on the same page.