What the Expression Language test button actually tests in the Fusion Application Page Composer

So you are customizing a page in Fusion Applications using the Page Composer. You come up with a nice way of using the Expression Language to hide a field dynamically based on the value of another field on the page. You type an expression in the Show Component property of the field and click on the Test button. And… Oops! It did not return the expected value. You check and double check the expression. It looks fine. You are starting to wonder whether this is a bug. But then something strikes you. You think you know what is happening. You check and confirm your hunch. You condense the lesson you learn in the picture below:

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