Our primary motivation was being able to build a static website as easy as using WordPress - so we figured, why not turn WordPress into a static site generator?
As notacoward mentioned, there is a few gotchas so we decided to launch it as a SaaS in order to abstract those things away and make it fully hosted on a CDN out of the box. We still give you full access to the WP install though, so no vendor-lock in or shackles for the customer.
Happy to give anyone a demo if you're interested. You can contact me at mathias AT dotsqua.re