Spring

Spring is very popular enterprise Java framework. I am not its user or big fan, so I am not afraid to conclude that it is the sole reasons why:

each enterprise error report contains at least 90% of useless reflection related stacktrace lines
it is impossible to debug the XML based configuration and find out why certain references points exactly to the value it points to
it takes seconds before Java enterprise application starts (compared to few ms before a NodeJS app starts)
users coding in other languages think Java is crazy (think of BeanFactory, BeanFactoryFactory, etc.)

The Spring framework is one of the reasons why Java is becoming the new COBOL!