The biggest factor preventing results is a focus on technical factors rather than a focus on key results. Often the plan to obtain the results are not aligned to the objectives. However, many projects do not have enough oversight, so no one identifies the lack of alignment. Without that identification of misalignment, course corrections cannot occur. (https://www.pmi.org/learning/library/seven-causes-project-failure-initiate-recovery-7195
Discenza, R. & Forman, J. B. (2007). Seven causes of project failure: how to recognize them and how to initiate project recovery. Paper presented at PMI® Global Congress 2007—North America, Atlanta, GA. Newtown Square, PA: Project Management Institute.)
However, sometimes the organization is not equipped to make those course corrections fast enough. The learning curve to manage to key results often takes 6 months or more. Sometimes the organization can't wait 6 months to begin making improvements. Often a little assistance is needed.