I am cheating just a bit with this challenge, as this
is one of the ones from my new book Data Modeling Made Simple-- but I thought it would be fun to share with the group:

Assume there is a rule in your company that an employee can work for one and only one manager. A modeler you work with is working on a human resource logical data model and has modeled the management hierarchy as shown in the following entity. She would like to know your thoughts on this. What are the pros and cons with using this entity to represent this business rule?