[theoctopus]

The main advantage of a static site generator is it allows you to just write the contents of each page and the generator will insert that into a page template. It means that, for example, a site-wide navbar only needs to be written once rather than added to every page manually.

[nine_k]

Even more importantly, if you change the navbar, it changes everywhere, no chance to forget, no tedious and error-prone copy-pasting.

Also, applying syntax highlighting to code fragments, doing the right thing around pictures, e.g. set explicit size, and many other seemingly trivial but tedious things.

In short, static site generators remove the legwork from static HTML.

[mixmastamyk]

All these reasons and it sucks to write html by hand compared to markdown or rst.