Is Java really slow?

Answer 1

Java WAS slow, back in the day. It has become much faster, due to a few generations of performance enhancements. Last I heard, it is usually within 10% of C# speed -- sometimes faster, sometimes slower.

Java applet startup is still slow because you've got to start a whole JVM, which has to load all it's classes. Somewhat like booting another computer. Once the JVM starts it is quite fast, but the startup is usually what people remember.

Also, there are at least a few people that will never believe in the viability of Java.