When developing a Minimal Viable Product (MVP), it’s usually best to release your web application quickly in order to test the marketability of your idea. Developing an application with Rails is usually much faster than if you would have used another programming language.
It’s possible to develop an application using Rails in a shorter time than if you used other programming languages. The time saved developing the application reduces the development cost. There is an an old saying: “Time is Money”
Easy to expand
It’s possible to expand Minimal Viable Product (MVP) into full-featured Ruby on Rails web application. There is no reason to start over when you expand the Minimal Viable Product.