It's not polite to eavesdrop on people.
Jenny has finished her work and has to wait for her coworker, Ellen, to get off the phone, so they can leave together.
Jenny wants to find something to do.
Jenny sits in her office and plans the next day's work while she waits for Ellen.
Jenny stands next to her Ellen's office door and listens in on her phone call.
Jenny is able to keep busy and Ellen can have privacy during her phone call.
Ellen notices that Jenny is listening to her conversation and asks Jenny to give her some privacy.