As organizations grow they often “adopt” an organizational structure that works best for them at the time. Organizational design is (or should be) fluid. This means revisiting the design and plans once, or preferably twice, each year and then using this as your bellwether for the organizational goal.
Organizational design begins by stating the business strategy as well as operational goals, and then diagramming an organization that is appropriate to meet those goals. Organizational design planning allows you to identify mission critical roles and prioritize bringing them on board.
For a growing business organizational design is a never-ending pursuit. Often an outside advisor can help you to identify the best options.