A study by Google showed that 53% of visits are likely to be abandoned if pages take longer than 3 seconds to load.
Their
Mobile First Indexing update favors mobile site load speed. The faster the website is on mobile, the better the chance of ranking higher.
Static hand-coded websites usually perform better than dynamic page builder websites like WordPress because they are faster.
When loading a static site, the browser reads and compiles the code and assets for the website and loads it. Every user loads the same content and there are no databases.
A dynamic site's code and assets are stored on a database. When loading a dynamic site, instead of the browsers compiling the code and assets, it’s a server that compiles it for the browser and sends it off, and instead of every user being served the exact same content they are all served different content individually.
A lot of people use WordPress, Wix, Squarespace, GoDaddy, etc. and there are many embedded scripts and plugins to support all their different needs. This produces heavy code making the process of putting the website together and sending it off take longer.
But even though hand-coded websites usually perform better because their code is lighter because they support the needs of one business, they usually cost more. We've tried to remedy this with our price model because it's hard to pay 50% upfront if you are not 100% convinced.