It’s not just failures; it’s the reasons why projects and programs are still failing. PMO (Project Management Office) and program/project managers have the responsibility for the coordination and the team's execution of the master plans, resource management to accomplish the tasks, and meeting the milestones with quality products or documents that meet or exceed the requirements of the project, product and company. But because of inadequate or incomplete planning and the lack of complete or stable requirements that were not or are not completed for development, all or many items are being done in parallel but with a reduced timeline for the project. And as seen, resource requirements have already been an issue.
…and it doesn’t matter what size business because this has been the mistake of small, medium, and large businesses (several million to billion dollars companies).