To be honest, that was its strength. It was brilliant largely for what it left out. I think it was largely successful as a language that superficially looked like C++ but without the sharp edges and foot guns. Also, it largely succeeded at being easy to learn, portable, memory safe, and reasonably secure. Once the HotSpot JIT was added, performance was actually quite good as well. The biggest issue Java had was that it never had a GUI toolkit that was pleasant for both developers and end users.