On the use of adding Variants to a Resource

[Mark Petrovic]

Good day.

The FirstResource reference app makes it clear that a Resource can  
have Variants added to it, and that entity variants can be tested in  
the event of the GET, POST, etc, received operations.  But it doesn't  
make clear why, in a Resource's constructor, those Resource's Variants  
are actually set or for whose consumption.  In other words, in what  
scenarios beyond setting a new Variant in the Resource constructor are  
the results of getVariants() used by an application?

Thanks.