According to Amelia Earhart, the first woman to fly solo across the Atlantic: “The time to worry is three months before a flight. Decide then whether or not the goal is worth the risks involved. If it is, stop worrying. To worry is to add another hazard.“
Likewise, for project managers, the time to worry is at the start of the project, months or years before the rollout. In addition to the risks of the project, consider the risk to your career. Like it or not, the success or failure of your career is bound up with the success or failure of the projects you lead.