Listen to and listen for

Listen to and listen for
 

When do we use listen for?
Is there a rule?
E.g. Listen for specific information, listen for the general idea, listen for the clue etc...

You listen to something which is actually happening

I listen to the radio
I listen to the birds singing

You listen for something which is not happening, but might happen

I listen for the noise of thunder (which hasn't happened yet)
I listen for the weather forecast (i.e. I am listening to the radio because I expect the weather forecast to happen soon)

I listen to a lecture, but I listen for an opportunity to spot mistakes in it

Thank you !