Ooops
Has someone ever told you a story and as it's coming to an end, you realize that you haven't been paying attention and have no idea what the person just said? You then have to gauge their vibe to try to figure out what reaction you should be having and it undoubtedly comes across as phoney. Then, as you discuss it a bit further, you have to try to go back and ask questions about aspects of their story without leading them to realize that you just weren't paying attention at all. I hate that.