Do i need both WebVirtualDir Alias ​​and WebApplication name in wix?

I understand that if I want wix to install a web application, I need to specify the virtual directory and then either paste <iis:WebApplication>

(as shown below) or link to the link from the attribute WebApplication

.

<iis:WebVirtualDir Id="myVirtualDir" Alias="NameThatShowsUpInIIS" Directory="INSTALLFOLDER" WebSite="myWebSite">
  <iis:WebApplication Id="myWebApp" Name="WhatIsThisFor" WebAppPool="myAppPool"/>
</iis:WebVirtualDir>

      

        
        
        
      

    

In IIS this only shows up as a web app under the website and there is only one name (the name of the virtual directory as given in Wix). What is the point of required attribute Name

for WebApplication?