ASP.NET Localize

A simple question. I have a site with localization (with .resx files) and when i need to insert localized text i use a code like this:

<asp:Localize Text="<%$ Resources: MyResource, Default_BannerHomeTitle %>" runat="server">SOME_TEXT_HERE_OR_NOT?</asp:Localize>
 

The question is if anyone knows what's the utility of the text between the asp:Localize tag -> "SOME_TEXT_HERE_OR_NOT?"

The real value come from the .resx file and the text "SOME_TEXT_HERE_OR_NOT?" is obviusly deleted when the page is rendered.

Is this text used in some situation? or is never used?

thanks in advance!

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