Because it "just works" and no other platform has yet convinced me that it is sufficiently better to justify the investment of time and energy which would be required to switch.<p>Take Netbeans - I've tried it, and it's nice enough. But it never wowed me as being so much better that I could justify throwing away all the accumulated knowledge and experience of dealing with Eclipse that I've built up over the years.<p>IntelliJ? For years was purely a closed-source, proprietary program which completely ruled it out from the get-to. Now, they have some kinda open-source'ish "community edition" or something, but I still think of their outfit as being largely a vendor of proprietary crap, which diminishes my interest in investing time there.<p>And outside of Eclipse, Netbeans, and IntelliJ, what is there in the Java world?<p>Sure, Eclipse has its flaws, and performance has always been one, but, for my purposes anyway, it remains "good enough".