You would think it would be an easy enough competence to listen, then speak, listen, then speak and so construct with another person a conversation, but this art is not always accomplished proficiently. Here are three types of incompetence I have recently come up against.
Monsieur A listens to what you say, then picks up on a detail and uses that as the impulse for his response. You gymnastically and skillfully re-formulate a response to adapt to the detail, whereupon he finds another peripheral detail from your latest response and picks up on that. Monsieur A can only converse through marginalia.
Madame B says something. You are in the middle of your response when you notice she is talking at the same time in an undertone, commenting immediately on what you are saying, so that two voices are happening simultaneously. Madame B can only converse through constant drone.
Monsieur C does not deign to engage in conversation unless he is a specialist in the matter and will come up trumps. If tricked into dialogue and revealed to be found wanting on some fact that should fall within his supposed province, he will crow I knew that!, as though he were a recalcitrant schoolboy. Monsieur C is in his late sixties. Monsieur C can only converse when he sees the imminence of his own triumph.
Yes, there are many ways to fail in the seemingly simple art of conversation.