I wrote another comment where I explained "popular due to jvm" better - the productivity gain was real, but came from the GC which was....JVM. No, the JVM wasn't hated initially - not until it became hugely popular and people started pushing it to the limit. Or well, at least that's how I remember the history, I might be wrong; human brains are notoriously fallible and I'm too lazy to search and validate/confirm my version of it :)