1. Work out what you want to build, and functionalities that you would require. 2. Do a search for libraries in language X. If success, go to 3 else it is dead for you - look at another language. 3. Look for adequate documentation and an active, helpful community. If success, go to 4 else it is dead for you - look at another language. 4. Try building a quick and simple application. If you found it enjoyable and offers something other tools you already know don't, go to 5 else it is dead for you - look at another language. 5. Build something more substantial. If you still find it enjoyable, go to 6 else it is dead for you - look at another language. 6. Congratulate yourself that you have discovered an enjoyable and useful tool. And that you took the time and effort to explore the language yourself and made an informed decision, and not just read someone's opinion and went with it. You may also start to suspect most opinions are from people who never actually used the language for anything more that what you just did, or inherited a dreadful codebase.

I did all this and I found myself using Pharo about three years ago. I still am, and I enjoy it tremendously. Also, (Pharo) Smalltalk is the most alive language I have ever used.