Is it a waste of time to use "Build Automatically" option for Java projects in Eclipse?

I'm developing J2EE webapps in Eclipse (RAD, actually). I've always used the "Project > Build automatically" option. However, I noticed that this isn't always necessary because Eclipse seems to push out changes to my server when I save a file. This works great but I'm wondering why this would be 开发者_StackOverflowchecked by default.

I can think of a few times when it makes sense to fully build and deploy the app:

• After changing a XML configuation file that gets loaded at app startup (application.xml, web.xml, bean configuration xml files, etc)
• After changing a static variable on a class

Other than this, I can't think of other times when it would be crucial (or useful) to enable the build automatically option. Am I incorrect in my above assumptions? Am I just wasting a bunch of time by building automatically??

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The automatic build compiles in the first-place. You can disable the automatic publishing (see screen) if you double-click on the server in the server-view. The automatic publishing has nothing to do with automatic build.