Humans are avid explainers: we ask “why?” and derive satisfaction from a good answer. But humans are also selective explainers: only some observations prompt us to ask “why?”, and only some answers are satisfying. This article reviews recent work on selectivity in explanation-seeking curiosity and explanatory satisfaction, with a focus on how this selectivity makes us effective learners in a complex world. Research finds that curiosity about the answer to a why-question is stronger when it is expected to yield useful learning, and that explanations are judged more satisfying when they are perceived to support useful learning. While such perceptions are imperfect, there is nonetheless evidence that seeking and evaluating explanations – in the selective way humans do – can play an important role in learning.