When developing a new program, it's good to try to get some kind of end-to-end thing work as soon as possible, even if it does nothing actually useful. A "hello, world" type of thing. This means you have to solve things like running and deployment, and it's massively easier to get those working at all if things are small and simple, rather than, say, retrofitting production deployment stuff into something that's been developed in "debug mode" all its life.