Enrichment refers to the practice of actively engaging and stimulating a list or audience in order to increase their value. This can be accomplished through targeted content and offers that cater to their specific interests and pain points. List building, an important aspect of marketing, also plays a key role in enrichment as it allows for more focused and personalized outreach. By constantly adding high-quality leads, businesses can continuously grow and engage their list, ultimately driving higher conversions and ROI.