The document outlines 12 common reasons why agencies lose proposals when trying to win new business. It discusses how agencies often treat proposals as a first step in the sales process rather than a final confirmation of discussions. Key reasons for losing proposals include focusing on costs rather than value, not properly qualifying prospects, failing to develop relationships with prospects, not acting like a true partner, using the wrong pricing framing, not having a standardized process, poor expectations setting, lack of follow up persistence, lack of credibility in proposals, and not challenging clients' assumptions about what they need. The document provides advice on how agencies can improve their proposal success rate by addressing these common shortcomings.