Heap emphasizes the importance of activation as a key metric for product teams to drive customer retention and value, particularly during the onboarding phase. By identifying and analyzing specific user actions, such as saving reports and using the "Group By" feature, Heap correlates these activities with higher long-term user engagement. The company uses both quantitative and qualitative data to address customer needs and improve the onboarding process, which is crucial for enhancing activation rates. Heap's onboarding strategy includes a product-health metric that helps the customer success team tailor their approach and identify at-risk users early, allowing for timely interventions. By focusing on these metrics and strategies, Heap aims to better understand and improve the factors that lead to customer loyalty and product success.