asp.net configuration settings default documents

Question

 

Dear experts, I am need of your help.

I am .net developer (ofcourse not an overall expert). Recently i have bought a space to host a website.
One of the technical person there at Hosting told me to change my configuration settings. And said my configuration is not correct...

My web.config settings...

<system.webServer>
<defaultDocument>
<files>
<add value="home.aspx"/>
</files>
</defaultDocument>
</system.webServer>


they said to change the above settings to.....

<system.webServer>
<directoryBrowse enabled="false" />
<defaultDocument>
<files>
<clear />
<add value="home.aspx" />
<add value="Default.htm" />
<add value="Default.asp" />
<add value="index.htm" />
<add value="index.html" />
<add value="iisstart.htm" />
<add value="default.aspx" />
<add value="index.php" />
</files>
</defaultDocument>
</system.webServer>


My question is,, why i need those default documents when i don't have those in my website application?