Most people listen to reply, not to understand
Research on listening shows that while someone is speaking, most listeners are allocating mental resources to formulating their response rather than processing what's being said. This means large portions of conversations are functionally monologues that happen to alternate. The practice of active listening — suspending your response preparation and focusing entirely on understanding the speaker's meaning — is rarer than it sounds and immediately distinguishes you in any conversation.
The most powerful thing you can give someone in a conversation is your full attention.