Losing a major client is one of the most humbling experiences a leader can face. Early in my career, I believed that delivering results was enough. If the numbers were good, the relationship would take care of itself. I was wrong. When we lost that client, I did a deep dive into what went wrong. The product was solid. The delivery was on time. The metrics were strong. But somewhere along the way, we had stopped listening. We had become so focused on executing that we forgot to check whether we were executing the right things. The lesson: results without relationships are temporary. You can deliver exceptional value, but if the client does not feel heard, understood, and genuinely valued as a partner — not just a revenue line — they will eventually find someone who makes them feel that way. Since then, I have built every client relationship around a simple principle: listen before you solve. Ask before you assume. And never let the quality of your work become a substitute for the quality of your attention. The client we lost? We won them back 18 months later. Not with a better product. With a better relationship. What is the most important relationship lesson your career has taught you?