In order to answer this question, first we must understand the concept of corporate governance.
In recent times, corporate governance has taken the business world by storm. The idea, essentially, is about a system of balance, that incorporates maximum profit with longevity and sustenance.
When it comes to strategic planning, it is necessary to account for all the external variables that add to and effect your business. This includes stakeholders, i.e. Suppliers and customers, consumers etc. The essence of the concept falls around strategically maximising and maintaining external relationships in order to enhance and proliferate the brand, since a key rule in business is that the reputation of your company lies in the feedback of the customer.
Strategic planning also works internally, including relationships with employees and people on the inside. If this is managed successfully, corporate governance can run efficiently and the business is likely to boom and flourish.
I hope this answers your question.