Initiating, planning, executing, monitoring, and closing a project can be a daunting task, especially when not in a position to employ a full-time project manager. This task can be efficiently undertaken by project management consultants, specialized personnel who offer their expertise and knowledge on a contractual basis. They lend themselves to the strategic planning, effective execution, and successful completion of projects. However, before engaging their services, it is imperative to understand the multifaceted dynamics that surround their hiring and utilization.

Firstly, project management consultants are not merely hired hands, they are strategic partners. Contractual agreements often describe them as service providers, yet their role is much more profound. They offer a depth of experience and wealth of knowledge that prove invaluable to a project's lifecycle. Thus, it is beneficial to view their engagement from a strategic partnership perspective. The complexity of their role is similar to that of a chess player, planning moves several steps ahead, understanding the interplay of pieces, predicting opponent's moves, and adjusting strategies accordingly.

Secondly, hiring them does not absolve the organization of all project responsibilities. The Pareto Principle, also known as the 80/20 rule, can be applied here. While project management consultants take over a substantial part of the project processes, the organization still needs to maintain a 20% active involvement. This includes providing strategic direction, making key decisions, and creating an enabling environment for the consultant to thrive.

Thirdly, the hiring process should be meticulous and thorough. It should mimic the Heisenberg Uncertainty Principle in Quantum Mechanics, which states that the position and the velocity of an object cannot both be measured exactly, at the same time. In the context of hiring a project management consultant, this means one cannot gauge both the consultant's depth of knowledge and the value they will bring to the project simultaneously. Hence, it underlines the importance of a rigorous screening process that involves checking previous work history, testimonials, qualifications, and an interview process designed to test their problem-solving abilities.

Fourthly, project management consultants add value beyond the project lifecycle. Their impact stretches beyond the confines of a specific project. They often introduce new methodologies, systems, and procedures that boost efficiency and productivity, such as the Agile or Waterfall methodologies. These can be incorporated into the organization’s standard operations, thus enhancing long-term operational efficiency.

Fifthly, their cost should not be viewed as an expense, but as an investment. Economic theories suggest that there's no such thing as a free lunch, implying that every resource has a cost attached and nothing is truly free. When it comes to project management consultants, their fees are not just for their time and the work they execute. Rather, they are an investment in the expertise, knowledge, and strategic insight they bring to the organization, which often results in cost savings and improved productivity.

Lastly, the optimal utilization of project management consultants requires a clear understanding of their role, a thorough hiring process, strategic engagement, active involvement, and an investment mindset. These will ensure that the organization benefits maximally from the consultant's expertise and experience.

In conclusion, project management consultants offer a critical service in the successful execution of projects. They bring a depth of knowledge, strategic insight, and efficient project management methodologies that can enhance the project's success. Their value extends beyond the confines of a single project and can indeed contribute significantly to an organization's long-term success and growth. Understanding the dynamics surrounding their engagement is key to making the most of their services.