FROM DISCOVERY TO DISAPPOINTMENT Where Value Leaks Along the Project Chain In the oil and gas industry, project outcomes are rarely determined by a single critical mistake. More often, they are shaped by a series of reasonable assumptions—each individually justified, but collectively optimistic. This book presents a systematic exploration of how value is gradually lost between discovery and production. Starting from volume estimation and moving through recovery factors, well productivity, development concept design, drilling costs, facilities capacity, schedule execution, and infrastructure dependencies, it uncovers a consistent pattern: uncertainty is acknowledged early, but progressively compressed as decisions move forward. The result is not failure in the conventional sense—but underperformance relative to expectations. Rather than focusing on isolated technical issues, this book introduces a unified perspective: value leakage as a structural phenomenon. Key topics include: - The misuse of probabilistic estimates (P50, P90) in decision-making - Recovery factor optimism and its systemic drivers - The gap between appraisal data and full-field performance - Concept creep and its impact on capital efficiency - Cost escalation and schedule risk in execution - Infrastructure dependencies and late-stage fragility - Organizational and decision-making biases that reinforce optimism Each chapter concludes with decision-grade checklists, enabling readers to directly apply the insights in field development planning, project reviews, and investment decisions. This is not a textbook. It is a framework for thinking. Designed for engineers, asset teams, and industry professionals, this book aims to bridge the gap between technical analysis and real-world outcomes—helping readers make better decisions under uncertainty and protect value across the full project lifecycle.