Also, a lot of developers forget to it, but even if you start with a fast language down the line you will end up rewriting it. The problem is that requirements change a lot and because of that your application will often end up being a mess. For similar reason RDBMS is also better than NoSQL when starting a project.

When rewriting you already know how the project is now, so you can design your app around that, which makes things simpler and faster.