In the 21st century with fast growth of computer technology developers are facing challenges more than ever. Existing programming languages are sometimes not good enough for them to fulfill mission best possible way.
One such example is Java (but not the only one). Even with Java 8, Java did not bring all modern features that developers in the 21st century expected.
At the moment some new modern technologies are emerging. One of many is Swift, which is very popular. There are some other good examples: Ruby, Go, Haskel, Elixir, Scala as well as many others.
Some programming languages that are not so new to developers like Erlang and Python gained certain popularity because of new trends.
Each language offers some advantages. However, there is still space for new languages to come. That is how Kotlin is born, powerful object-oriented programming language.