Do you want more success in PM, clarify accountability.  HOWEVER, you must also ensure work is aligned with capability of the person.  Avoid those stretch goals that depend on hope and luck.

The conference I attended last week in New York (by the  GO Society )  focused much on Structure of the working team and ensuring each role matches up two key aspects:
1 - Current Applied Capability with
2 - complexity and time span of the work tasks

A great paper that introduces you to this fundamental principle which people naturally can see the logic and support was written by Don Fowke and Ken Sheppard (see link below)

Getting Work Done at the Right Levels

Even though many concepts of this Structured Approach (known as Requisite Organizational Design) are discussed in an operational sense of work, it very much aligns with Project Management.

If you do not have proper Governance in terms of Org Design, Accountability and cross matrix reporting relationships, then you will struggle the entire project.  By following principles of this approach, you can build your house on a strong concrete foundation (vs sand and wet mud).  Is not only important but is foundational.  This approach provides science and global experience to show that it works and has been working for decades.  It is also now being published in Educational learning materials that are easier to understand, easier to relate and integrate into our businesses.