Thoughts
I think Java is successful because it is a bad language.
Developers who program in a good language, one that they enjoy, don't leave home.
The enduring and defining trait of Java is not the standard library or the features or the syntax or even the problems it is designed to solve. The enduring trait of Java is its particular implementation of the Object Oriented Programming system. This system for writing and organizing code is unmatched in other languages. No one does Java like Java.
You would think that developers would use the most flexible system, but instead developers flock to the best implementation of the least flexible system.