Qualities of a Good Programming Language

• concise - a minimum of boilerplate, short but expressive keywords and built-in operators. Less keywords is not necessarily better than more, but shorter ones are.
• readable - apps written in some languages are easier to read and understand later, by original author and by others
• flexible - can be used in a variety of roles, the more the better because there's a certain overhead and learning curve a programmer has to climb (which may include tool acquisition and ecosystem acclimation) for each new language, and the more that a single language can fill multiple roles, the better. Example: glue scripts, and workflow automation, and testing, and web dev, etc.
• reliable - combination of bug-free and consistent and therefore predictable behavior when used (you can rely on a mental model in your head of how the app will behave at runtime)

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