The existence of a projectmanager keeps the focus on the product or service provided. 
 
 An example of a matrix structure at a software development company. Business analysts, developers, and testers each report to a functional department manager and to a project manager simultaneously. 
  
 Despite these potential benefits, matrix structures are not without costs. In a matrix, each employee reports to two or more managers. This situation is ripe for conflict. Because multiple managers are in charge of guiding the behaviors of each employee, there may be power struggles or turf wars among managers. As managers are more interdependent compared to a traditional or product-based structure, they will need to spend more effort coordinating their work. From the employee’s perspective, there is potential for interpersonal conflict with team members as well as with leaders. The presence of multiple leaders may create role ambiguity or, worse, role conflict—being given instructions or objectives that cannot all be met because they are mutually exclusive. The necessity to work with a team consisting of employees with different functional backgrounds increases the potential for task conflict at work. 

Solving these problems requires a great level of patience and proactivity on the part of the employee. 
 
 (Zain Books)