What is Get Desired Rotation?

Googling just leads me to a UE4 documentation that explains the pins, but I want to know how it functions and what it’s used for. I’m a visual guy, so a nice video of it being used would be amazing since there doesn’t seem to be any. If there are no videos, then some documentation with pictures (I really like pictures) would suffice.

For future googlers:

Since it looks like this in source:

FRotator AController::GetDesiredRotation() const
return GetControlRotation();

I think it was meant to be overridden in some AI controller implementation (but is not ) and returns current control rotation instead.