The creators and main contributors of Ruby on Rails take security very seriously. They have a whole process, described on their website in detail, for reporting, fixing, and rolling out security patches. Crucial security features come with the basic Rails package, and developers using the latest RoR version are updated about new security issues. [source]

Without Rails, Ruby might not have become a popular programming language for web applications. Which is a great thing because Ruby is driven by a unique philosophy, and it makes programmers happy. [source]

It’s easy to learn - especially if you have experience working with programming languages like Python or PHP. [source]

Building an application from the ground up is much faster compared to using other popular technologies.

It’s a pragmatic language, and pragmatism is visible in the whole culture of Ruby on Rails. Compared to other languages and frameworks, there is very little artificial complexity in RoR. [source]

Unlike many other technologies that have been around for 10+ years, Rails is still being updated. Rails is a stable technology that is evolving without any major breaking changes. [source]

Rails makes it easy for programmers to switch between projects because the philosophy and software development principles are always the same. [source]

The community around Ruby on Rails is a wonderful thing in and of itself. Development of RoR is still managed by its original creator. The amount of programmers using RoR keeps growing. New gems are constantly being added to public repositories. This is very different from other popular frameworks, and it’s a huge selling point for this technology. [source]

There are easy ways to integrate Rails with popular front-end frameworks, as well as other third-party technologies for web development.

Ruby on Rails is free. There are no licensing fees. The base package, all the support resources, as well as endless open-source code libraries — you can download it all and use it without paying a cent.

RoR is flexible. As projects grow in complexity, sometimes developers realise that they need to make fundamental changes to the codebase, like changing the database engine. In Rails, things like this are very easy to do, and don’t require any changes in the application code. [source]

Rails makes it easy to build automated tests, which translates to less time spent debugging in late stages of development. [source]

It is a mature technology. Even though the heyday of RoR is over, the community hasn’t stopped growing, and Rails is still being improved. Very few technologies have had so much luck for so many years, which goes to show that RoR is simply a great tool. [source]

Rails is a tool that works well in various scenarios. It’s good for large, modern, public websites, as well as complicated in-house enterprise applications using insane business rules and logic. [source]

RoR is readable, easy to maintain, and productive. It enables developers to work on high-level software issues, instead of micromanaging the codebase of their apps. [source]

Contained in Ruby on Rails is a whole suite of solutions for various common problems that developers face when building applications. There are a lot of ready-made, tested functionalities that can be implemented as plugins. Together with gems, this makes development much faster, and much easier.

The Ruby on Rails documentation is clear, concise, and makes it easy to find solutions for every problem you might encounter. [source]