Project managers would not be needed if everyone did exactly what they are supposed to do when they are supposed to do it. In that idealistic universe we would only need traffic managers to ensure that everyone knew what needed to be done.
Fortunately (at least for pm professionals) this ideal universe is as elusive as an unambiguous requirements document. Projects are executed by people and are prone to the inevitable reality of human error. Varying opinions and unjustified assumptions lead project managers to be required to study the complexities of the human spirit.
Emotional intelligence, empathy and listening skills are critical in creating and maintaining an environment that leads to collaboration, motivation, engagement and creativity.
Requirements management and communication are consistently identified in studies as the top areas to focus on in order to resolve the most common causes of project failure. The relationship between these areas is obvious and yet so often overlooked or misinterpreted. Communication is more than ensuring that a message is sent and received. Our responsibility as a project manager is to ensure that the message is understood. Application of this principle throughout the project life-cycle dramatically improves the likelihood of success.
Finally, success has to be measured not only in requirement satisfaction and performance against the baseline. We need to include as a success measure the overall engagement and satisfaction of the project team members before, during, and after the project to ensure that we are truly paying attention to our most important asset.